diff --git a/src/UniTask/Assets/Plugins/UniTask/Runtime/UnityAsyncExtensions.cs b/src/UniTask/Assets/Plugins/UniTask/Runtime/UnityAsyncExtensions.cs
index 9a85e37..1817d11 100644
--- a/src/UniTask/Assets/Plugins/UniTask/Runtime/UnityAsyncExtensions.cs
+++ b/src/UniTask/Assets/Plugins/UniTask/Runtime/UnityAsyncExtensions.cs
@@ -160,7 +160,7 @@ namespace Cysharp.Threading.Tasks
             }
 
             public bool MoveNext()
-            {
+            {   
                 if (completed)
                 {
                     TryReturn();
@@ -466,7 +466,7 @@ namespace Cysharp.Threading.Tasks
             }
 
             public bool MoveNext()
-            {
+            {   
                 if (completed)
                 {
                     TryReturn();
@@ -776,7 +776,7 @@ namespace Cysharp.Threading.Tasks
             }
 
             public bool MoveNext()
-            {
+            {   
                 if (completed)
                 {
                     TryReturn();
@@ -1086,7 +1086,7 @@ namespace Cysharp.Threading.Tasks
             }
 
             public bool MoveNext()
-            {
+            {   
                 if (completed)
                 {
                     TryReturn();
@@ -1285,12 +1285,20 @@ namespace Cysharp.Threading.Tasks
                     continuationAction = null;
                     var result = asyncOperation.webRequest;
                     asyncOperation = null;
+                    if (result.isHttpError || result.isNetworkError)
+                    {
+                        throw new UnityWebRequestException(result);
+                    }
                     return result;
                 }
                 else
                 {
                     var result = asyncOperation.webRequest;
                     asyncOperation = null;
+                    if (result.isHttpError || result.isNetworkError)
+                    {
+                        throw new UnityWebRequestException(result);
+                    }
                     return result;
                 }
             }
@@ -1367,7 +1375,15 @@ namespace Cysharp.Threading.Tasks
                 else
                 {
                     completed = true;
-                    core.TrySetResult(asyncOperation.webRequest);
+                    var result = asyncOperation.webRequest;
+                    if (result.isHttpError || result.isNetworkError)
+                    {
+                        core.TrySetException(new UnityWebRequestException(result));
+                    }
+                    else
+                    {
+                        core.TrySetResult(result);
+                    }
                 }
             }
 
@@ -1397,7 +1413,7 @@ namespace Cysharp.Threading.Tasks
             }
 
             public bool MoveNext()
-            {
+            {   
                 if (completed)
                 {
                     TryReturn();
@@ -1526,7 +1542,14 @@ namespace Cysharp.Threading.Tasks
 
                 if (asyncOperation.isDone)
                 {
-                    core.TrySetResult(asyncOperation.webRequest);
+                    if (asyncOperation.webRequest.isHttpError || asyncOperation.webRequest.isNetworkError)
+                    {
+                        core.TrySetException(new UnityWebRequestException(asyncOperation.webRequest));
+                    }
+                    else
+                    {
+                        core.TrySetResult(asyncOperation.webRequest);
+                    }
                     return false;
                 }
 
diff --git a/src/UniTask/Assets/Plugins/UniTask/Runtime/UnityAsyncExtensions.tt b/src/UniTask/Assets/Plugins/UniTask/Runtime/UnityAsyncExtensions.tt
index 93701ef..61279a3 100644
--- a/src/UniTask/Assets/Plugins/UniTask/Runtime/UnityAsyncExtensions.tt
+++ b/src/UniTask/Assets/Plugins/UniTask/Runtime/UnityAsyncExtensions.tt
@@ -81,6 +81,12 @@ namespace Cysharp.Threading.Tasks
 <# if (!IsVoid(t)) { #>
                     var result = <#= $"asyncOperation.{t.returnField}" #>;
                     asyncOperation = null;
+<# if(t.returnType == "UnityWebRequest") { #>
+                    if (result.isHttpError || result.isNetworkError)
+                    {
+                        throw new UnityWebRequestException(result);
+                    }
+<# } #>
                     return result;
 <# } else { #>
                     asyncOperation = null;
@@ -91,6 +97,12 @@ namespace Cysharp.Threading.Tasks
 <# if (!IsVoid(t)) { #>
                     var result = <#= $"asyncOperation.{t.returnField}" #>;
                     asyncOperation = null;
+<# if(t.returnType == "UnityWebRequest") { #>
+                    if (result.isHttpError || result.isNetworkError)
+                    {
+                        throw new UnityWebRequestException(result);
+                    }
+<# } #>
                     return result;
 <# } else { #>
                     asyncOperation = null;
@@ -170,7 +182,19 @@ namespace Cysharp.Threading.Tasks
                 else
                 {
                     completed = true;
+<# if(t.returnType == "UnityWebRequest") { #>
+                    var result = asyncOperation.webRequest;
+                    if (result.isHttpError || result.isNetworkError)
+                    {
+                        core.TrySetException(new UnityWebRequestException(result));
+                    }
+                    else
+                    {
+                        core.TrySetResult(result);
+                    }
+<# } else { #>
                     core.TrySetResult(<#= IsVoid(t) ? "AsyncUnit.Default" : $"asyncOperation.{t.returnField}" #>);
+<# } #>
                 }
             }
 
@@ -345,7 +369,18 @@ namespace Cysharp.Threading.Tasks
 
                 if (asyncOperation.isDone)
                 {
+<# if(t.returnType == "UnityWebRequest") { #>
+                    if (asyncOperation.webRequest.isHttpError || asyncOperation.webRequest.isNetworkError)
+                    {
+                        core.TrySetException(new UnityWebRequestException(asyncOperation.webRequest));
+                    }
+                    else
+                    {
+                        core.TrySetResult(asyncOperation.webRequest);
+                    }
+<# } else { #>
                     core.TrySetResult(<#= IsVoid(t) ? "AsyncUnit.Default" : $"asyncOperation.{t.returnField}" #>);
+<# } #>
                     return false;
                 }
 
diff --git a/src/UniTask/Assets/Plugins/UniTask/Runtime/UnityWebRequestError.cs b/src/UniTask/Assets/Plugins/UniTask/Runtime/UnityWebRequestError.cs
new file mode 100644
index 0000000..c5fe3ff
--- /dev/null
+++ b/src/UniTask/Assets/Plugins/UniTask/Runtime/UnityWebRequestError.cs
@@ -0,0 +1,24 @@
+#if ENABLE_UNITYWEBREQUEST
+
+using System;
+using UnityEngine.Networking;
+
+namespace Cysharp.Threading.Tasks
+{
+    public class UnityWebRequestException : Exception
+    {
+        public UnityWebRequest UnityWebRequest { get; }
+        public bool IsNetworkError { get; }
+        public bool IsHttpError { get; }
+
+        public UnityWebRequestException(UnityWebRequest unityWebRequest)
+            : base(unityWebRequest.error + Environment.NewLine + unityWebRequest.downloadHandler.text)
+        {
+            this.UnityWebRequest = unityWebRequest;
+            this.IsNetworkError = unityWebRequest.isNetworkError;
+            this.IsHttpError = unityWebRequest.isHttpError;
+        }
+    }
+}
+
+#endif
\ No newline at end of file
diff --git a/src/UniTask/Assets/Plugins/UniTask/Runtime/UnityWebRequestError.cs.meta b/src/UniTask/Assets/Plugins/UniTask/Runtime/UnityWebRequestError.cs.meta
new file mode 100644
index 0000000..50c475e
--- /dev/null
+++ b/src/UniTask/Assets/Plugins/UniTask/Runtime/UnityWebRequestError.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 013a499e522703a42962a779b4d9850c
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/src/UniTask/Assets/Scenes/SandboxMain.cs b/src/UniTask/Assets/Scenes/SandboxMain.cs
index d9a765a..9dacea2 100644
--- a/src/UniTask/Assets/Scenes/SandboxMain.cs
+++ b/src/UniTask/Assets/Scenes/SandboxMain.cs
@@ -415,15 +415,12 @@ public class SandboxMain : MonoBehaviour
 
     private async UniTaskVoid ExecuteAsync()
     {
-        Debug.Log("1");
-        {
-            var xs = await UniTaskAsyncEnumerable.TimerFrame(1).ToArrayAsync();
-        }
-        Debug.Log("------------------");
-        {
-            var xs = await UniTaskAsyncEnumerable.TimerFrame(1).ToArrayAsync();
-            Debug.Log("2");
-        }
+        var req = UnityWebRequest.Get("https://google.com/");
+
+        var v = await req.SendWebRequest().ToUniTask();
+        // req.Dispose();
+        Debug.Log($"{v.isDone} {v.isHttpError} {v.isNetworkError}");
+        Debug.Log(v.downloadHandler.text);
     }
 
 
@@ -446,7 +443,7 @@ public class SandboxMain : MonoBehaviour
         // rp.AddTo(this.GetCancellationTokenOnDestroy());
         var cts = new CancellationTokenSource();
 
-        
+