diff --git a/hutool-crypto/src/main/java/org/dromara/hutool/crypto/bc/ECKeyUtil.java b/hutool-crypto/src/main/java/org/dromara/hutool/crypto/bc/ECKeyUtil.java
index 2ce7e5940..2e28034c1 100644
--- a/hutool-crypto/src/main/java/org/dromara/hutool/crypto/bc/ECKeyUtil.java
+++ b/hutool-crypto/src/main/java/org/dromara/hutool/crypto/bc/ECKeyUtil.java
@@ -49,6 +49,7 @@ import java.security.PrivateKey;
 import java.security.PublicKey;
 import java.security.spec.ECPublicKeySpec;
 import java.security.spec.KeySpec;
+import java.util.Objects;
 
 /**
  * 椭圆曲线EC(Elliptic Curves)密钥参数相关工具类封装
@@ -339,7 +340,9 @@ public class ECKeyUtil {
 		if (null == d) {
 			return null;
 		}
-		return toPrivateParams(BigIntegers.fromUnsignedByteArray(SecureUtil.decode(d)), domainParameters);
+		return toPrivateParams(
+			BigIntegers.fromUnsignedByteArray(Objects.requireNonNull(SecureUtil.decode(d))),
+			domainParameters);
 	}
 
 	/**
diff --git a/hutool-crypto/src/test/java/org/dromara/hutool/crypto/asymmetric/Issue3728Test.java b/hutool-crypto/src/test/java/org/dromara/hutool/crypto/asymmetric/Issue3728Test.java
new file mode 100644
index 000000000..a2294d0c0
--- /dev/null
+++ b/hutool-crypto/src/test/java/org/dromara/hutool/crypto/asymmetric/Issue3728Test.java
@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2024 Hutool Team and hutool.cn
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.dromara.hutool.crypto.asymmetric;
+
+import org.junit.jupiter.api.Test;
+
+public class Issue3728Test {
+	@Test
+	void sm2Test() {
+		String  publicKey="04beab9c2b800c03263b2d9cfcc832eb6827d5b62dc2ec7f8503c8832799af13b057d6b5bf5bc6c144753f3aa8b6cef8acb00a379a4fbed2f90c546fc2b4586bb0";
+		String  privateKey="3920cfc4828339b34da62b97b44d49d3a9c7dc84d9e6732d4b18f681a339519c";
+		final SM2 sm2 = new SM2(privateKey, publicKey);
+	}
+}