diff --git a/CHANGELOG.md b/CHANGELOG.md
index 779fdec9e..92915ce9c 100755
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@
 ### 🐞Bug修复
 * 【extra  】     修复createExtractor中抛出异常后流未关闭问题（pr#2384@Github）
 * 【core   】     修复CsvData.getHeader没有判空导致空指针问题（issue#I5CK7Q@Gitee）
+* 【core   】     修复单字母转换为数字的问题（issue#I5C4K1@Gitee）
 
 -------------------------------------------------------------------------------------------------------------
 
diff --git a/hutool-core/src/main/java/cn/hutool/core/convert/impl/NumberConverter.java b/hutool-core/src/main/java/cn/hutool/core/convert/impl/NumberConverter.java
index 421628c91..1a2837ff1 100644
--- a/hutool-core/src/main/java/cn/hutool/core/convert/impl/NumberConverter.java
+++ b/hutool-core/src/main/java/cn/hutool/core/convert/impl/NumberConverter.java
@@ -68,7 +68,7 @@ public class NumberConverter extends AbstractConverter<Number> {
 	@Override
 	protected String convertToStr(Object value) {
 		String result = StrUtil.trim(super.convertToStr(value));
-		if (StrUtil.isNotEmpty(result)) {
+		if (null != result && result.length() > 1) {
 			final char c = Character.toUpperCase(result.charAt(result.length() - 1));
 			if (c == 'D' || c == 'L' || c == 'F') {
 				// 类型标识形式（例如123.6D）
diff --git a/hutool-core/src/test/java/cn/hutool/core/map/MapUtilTest.java b/hutool-core/src/test/java/cn/hutool/core/map/MapUtilTest.java
index aa667dc45..0f371b072 100644
--- a/hutool-core/src/test/java/cn/hutool/core/map/MapUtilTest.java
+++ b/hutool-core/src/test/java/cn/hutool/core/map/MapUtilTest.java
@@ -217,4 +217,11 @@ public class MapUtilTest {
 		Assert.assertEquals(Integer.valueOf(1), map.get("a"));
 		Assert.assertEquals(Integer.valueOf(2), map.get("b"));
 	}
+
+	@Test(expected = NumberFormatException.class)
+	public void getIntTest(){
+		final HashMap<String, String> map = MapUtil.of("age", "d");
+		final Integer age = MapUtil.getInt(map, "age");
+		Assert.assertNotNull(age);
+	}
 }
diff --git a/hutool-core/src/test/java/cn/hutool/core/util/NumberUtilTest.java b/hutool-core/src/test/java/cn/hutool/core/util/NumberUtilTest.java
index 4368ada2f..d4ab4b079 100644
--- a/hutool-core/src/test/java/cn/hutool/core/util/NumberUtilTest.java
+++ b/hutool-core/src/test/java/cn/hutool/core/util/NumberUtilTest.java
@@ -287,6 +287,12 @@ public class NumberUtilTest {
 		Assert.assertEquals(1482, v1);
 	}
 
+	@Test(expected = NumberFormatException.class)
+	public void parseIntTest3() {
+		int v1 = NumberUtil.parseInt("d");
+		Assert.assertEquals(0, v1);
+	}
+
 	@Test
 	public void parseNumberTest() {
 		// from 5.4.8 issue#I23ORQ@Gitee