diff --git a/plusone-system/plusone-system-application/src/main/java/xyz/zhouxy/plusone/system/application/service/AccountManagementService.java b/plusone-system/plusone-system-application/src/main/java/xyz/zhouxy/plusone/system/application/service/AccountManagementService.java
index 0eab48b..36050c3 100644
--- a/plusone-system/plusone-system-application/src/main/java/xyz/zhouxy/plusone/system/application/service/AccountManagementService.java
+++ b/plusone-system/plusone-system-application/src/main/java/xyz/zhouxy/plusone/system/application/service/AccountManagementService.java
@@ -69,7 +69,11 @@ public class AccountManagementService {
                 command.getPasswordConfirmation(),
                 command.getStatus(),
                 command.getRoleRefs(),
-                AccountInfo.of(command.getNickname(), command.getAvatar(), command.getSex()),
+                AccountInfo.builder()
+                        .nickname(command.getNickname())
+                        .avatar(command.getAvatar())
+                        .sex(command.getSex())
+                        .build(),
                 adminAuthLogic.getLoginIdAsLong());
         accountRepository.save(account);
     }
diff --git a/plusone-system/plusone-system-application/src/main/java/xyz/zhouxy/plusone/system/application/service/RegisterAccountService.java b/plusone-system/plusone-system-application/src/main/java/xyz/zhouxy/plusone/system/application/service/RegisterAccountService.java
index cfc3116..c81a49c 100644
--- a/plusone-system/plusone-system-application/src/main/java/xyz/zhouxy/plusone/system/application/service/RegisterAccountService.java
+++ b/plusone-system/plusone-system-application/src/main/java/xyz/zhouxy/plusone/system/application/service/RegisterAccountService.java
@@ -17,7 +17,6 @@ import xyz.zhouxy.plusone.system.domain.model.account.AccountStatus;
 import xyz.zhouxy.plusone.system.domain.model.account.Email;
 import xyz.zhouxy.plusone.system.domain.model.account.MobilePhone;
 import xyz.zhouxy.plusone.system.domain.model.account.Password;
-import xyz.zhouxy.plusone.system.domain.model.account.Sex;
 import xyz.zhouxy.plusone.system.domain.model.account.Username;
 
 /**
@@ -82,7 +81,9 @@ public class RegisterAccountService {
                 Password.newPassword(command.getPassword(), command.getReenteredPassword()),
                 AccountStatus.AVAILABLE,
                 Set.of(DEFAULT_ROLE_ID),
-                AccountInfo.of(command.getNickname(), null, Sex.UNSET));
+                AccountInfo.builder()
+                        .nickname(command.getNickname())
+                        .build());
         accountRepository.save(accountToSave);
     }
 
diff --git a/plusone-system/plusone-system-domain/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/Account.java b/plusone-system/plusone-system-domain/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/Account.java
index 895eda3..3150b64 100644
--- a/plusone-system/plusone-system-domain/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/Account.java
+++ b/plusone-system/plusone-system-domain/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/Account.java
@@ -93,11 +93,19 @@ public class Account extends AggregateRoot<Long> implements IWithVersion {
     }
 
     public void setAccountInfo(Nickname nickname, URL avatar, Sex sex) {
-        this.accountInfo = AccountInfo.of(nickname, avatar, sex);
+        this.accountInfo = AccountInfo.builder()
+                .nickname(nickname)
+                .avatar(avatar)
+                .sex(sex)
+                .build();
     }
 
     public void setAccountInfo(String nickname, String avatar, Sex sex) {
-        this.accountInfo = AccountInfo.of(nickname, avatar, sex);
+        this.accountInfo = AccountInfo.builder()
+                .nickname(nickname)
+                .avatar(avatar)
+                .sex(sex)
+                .build();
     }
 
     /**
diff --git a/plusone-system/plusone-system-domain/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/AccountInfo.java b/plusone-system/plusone-system-domain/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/AccountInfo.java
index 6b9aa87..7e750d0 100644
--- a/plusone-system/plusone-system-domain/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/AccountInfo.java
+++ b/plusone-system/plusone-system-domain/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/AccountInfo.java
@@ -5,7 +5,9 @@ import java.net.URL;
 import java.util.Objects;
 import java.util.Optional;
 
-import lombok.Getter;
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
 import lombok.ToString;
 import xyz.zhouxy.plusone.domain.IValueObject;
 
@@ -17,30 +19,19 @@ import xyz.zhouxy.plusone.domain.IValueObject;
 @ToString
 public class AccountInfo implements IValueObject {
 
+    @Nullable
     private final Nickname nickname;
+    @Nullable
     private final URL avatar;
-    private final @Getter Sex sex;
+    @Nonnull
+    private final Sex sex;
 
-    private AccountInfo(Nickname nickname, URL avatar, Sex sex) {
+    private AccountInfo(@Nullable Nickname nickname, @Nullable URL avatar, @Nullable Sex sex) {
         this.nickname = nickname;
         this.avatar = avatar;
         this.sex = Objects.nonNull(sex) ? sex : Sex.UNSET;
     }
 
-    public static AccountInfo of(Nickname nickname, URL avatar, Sex sex) {
-        return new AccountInfo(nickname, avatar, sex);
-    }
-
-    public static AccountInfo of(String nickname, String avatar, Sex sex) {
-        URL avatarURL;
-        try {
-            avatarURL = Objects.nonNull(avatar) ? new URL(avatar) : null;
-        } catch (MalformedURLException e) {
-            throw new IllegalArgumentException(e);
-        }
-        return new AccountInfo(Nickname.ofNullable(nickname), avatarURL, sex);
-    }
-
     public Optional<Nickname> getNickname() {
         return Optional.ofNullable(nickname);
     }
@@ -48,4 +39,54 @@ public class AccountInfo implements IValueObject {
     public Optional<URL> getAvatar() {
         return Optional.ofNullable(avatar);
     }
+
+    @Nonnull
+    public Sex getSex() {
+        return this.sex;
+    }
+
+    // Builder
+
+    public static Builder builder() {
+        return new Builder();
+    }
+
+    public static class Builder {
+        private Nickname nickname;
+        private URL avatar;
+        private Sex sex;
+
+        public Builder nickname(@Nullable Nickname nickname) {
+            this.nickname = nickname;
+            return this;
+        }
+
+        public Builder nickname(@Nullable String nickname) {
+            return nickname(Nickname.ofNullable(nickname));
+        }
+
+        public Builder avatar(@Nullable URL avatar) {
+            this.avatar = avatar;
+            return this;
+        }
+
+        public Builder avatar(@Nullable String avatar) {
+            URL avatarURL;
+            try {
+                avatarURL = Objects.nonNull(avatar) ? new URL(avatar) : null;
+            } catch (MalformedURLException e) {
+                throw new IllegalArgumentException(e);
+            }
+            return avatar(avatarURL);
+        }
+
+        public Builder sex(@Nullable Sex sex) {
+            this.sex = sex;
+            return this;
+        }
+
+        public AccountInfo build() {
+            return new AccountInfo(this.nickname, this.avatar, this.sex);
+        }
+    }
 }
diff --git a/plusone-system/plusone-system-domain/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/Sex.java b/plusone-system/plusone-system-domain/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/Sex.java
index 3b80c87..e7d5117 100644
--- a/plusone-system/plusone-system-domain/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/Sex.java
+++ b/plusone-system/plusone-system-domain/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/Sex.java
@@ -1,5 +1,7 @@
 package xyz.zhouxy.plusone.system.domain.model.account;
 
+import javax.annotation.Nonnull;
+
 import xyz.zhouxy.plusone.commons.util.Enumeration;
 import xyz.zhouxy.plusone.domain.IValueObject;
 
@@ -9,8 +11,11 @@ import xyz.zhouxy.plusone.domain.IValueObject;
  * @author <a href="https://gitee.com/zhouxy108">ZhouXY</a>
  */
 public class Sex extends Enumeration<Sex> implements IValueObject {
+    @Nonnull
     public static final Sex UNSET = new Sex(0, "未设置");
+    @Nonnull
     public static final Sex MALE = new Sex(1, "男性");
+    @Nonnull
     public static final Sex FEMALE = new Sex(2, "女性");
 
     private Sex(int value, String name) {
diff --git a/plusone-system/plusone-system-infrastructure/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/AccountRepositoryImpl.java b/plusone-system/plusone-system-infrastructure/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/AccountRepositoryImpl.java
index a700c63..32ec762 100644
--- a/plusone-system/plusone-system-infrastructure/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/AccountRepositoryImpl.java
+++ b/plusone-system/plusone-system-infrastructure/src/main/java/xyz/zhouxy/plusone/system/domain/model/account/AccountRepositoryImpl.java
@@ -176,10 +176,6 @@ public class AccountRepositoryImpl extends JdbcRepositorySupport<Account, Long>
     @Override
     protected final Account mapRow(ResultSet rs) throws SQLException {
         long accountId = rs.getLong("id");
-        AccountInfo accountInfo = AccountInfo.of(
-                rs.getString("nickname"),
-                rs.getString("avatar"),
-                Sex.of(rs.getInt("sex")));
         return new Account(
                 accountId,
                 rs.getString("username"),
@@ -187,7 +183,11 @@ public class AccountRepositoryImpl extends JdbcRepositorySupport<Account, Long>
                 rs.getString("mobile_phone"),
                 Password.of(rs.getString("password"), rs.getString("salt")),
                 AccountStatus.of(rs.getInt("status")),
-                accountInfo,
+                AccountInfo.builder()
+                        .nickname(rs.getString("nickname"))
+                        .avatar(rs.getString("avatar"))
+                        .sex(Sex.of(rs.getInt("sex")))
+                        .build(),
                 this.accountRoleDAO.selectRoleIdsByAccountId(accountId),
                 rs.getLong("created_by"),
                 rs.getLong("updated_by"),