diff --git a/Netch/Controllers/MainController.cs b/Netch/Controllers/MainController.cs
index b94b2136..4ff02304 100644
--- a/Netch/Controllers/MainController.cs
+++ b/Netch/Controllers/MainController.cs
@@ -61,7 +61,7 @@ namespace Netch.Controllers
             // 刷新DNS缓存
             NativeMethods.FlushDNSResolverCache();
 
-            if (DNS.Lookup(server.Hostname) == null)
+            if (DnsUtils.Lookup(server.Hostname) == null)
                 throw new MessageException(i18N.Translate("Lookup Server hostname failed"));
 
             // 添加Netch到防火墙
diff --git a/Netch/Controllers/TUNTAPController.cs b/Netch/Controllers/TUNTAPController.cs
index b88499a5..5a2671df 100644
--- a/Netch/Controllers/TUNTAPController.cs
+++ b/Netch/Controllers/TUNTAPController.cs
@@ -42,7 +42,7 @@ namespace Netch.Controllers
         public void Start(in Mode mode)
         {
             var server = MainController.Server!;
-            _serverAddresses = DNS.Lookup(server.Hostname)!; // server address have been cached when MainController.Start
+            _serverAddresses = DnsUtils.Lookup(server.Hostname)!; // server address have been cached when MainController.Start
 
             if (TUNTAP.GetComponentID() == null)
                 TUNTAP.AddTap();
@@ -72,7 +72,7 @@ namespace Netch.Controllers
                 argument.Append($"-proxyServer 127.0.0.1:{Global.Settings.Socks5LocalPort} ");
 
             argument.Append(
-                $"-tunAddr {Global.Settings.TUNTAP.Address} -tunMask {Global.Settings.TUNTAP.Netmask} -tunGw {Global.Settings.TUNTAP.Gateway} -tunDns {DNS.Join(dns)} -tunName \"{TUNTAP.GetName(_tap.ComponentID)}\" ");
+                $"-tunAddr {Global.Settings.TUNTAP.Address} -tunMask {Global.Settings.TUNTAP.Netmask} -tunGw {Global.Settings.TUNTAP.Gateway} -tunDns {DnsUtils.Join(dns)} -tunName \"{TUNTAP.GetName(_tap.ComponentID)}\" ");
 
             if (Global.Settings.TUNTAP.UseFakeDNS && Global.Flags.SupportFakeDns)
                 argument.Append("-fakeDns ");
diff --git a/Netch/Forms/MainForm.cs b/Netch/Forms/MainForm.cs
index 046e12c6..ee23dc8a 100644
--- a/Netch/Forms/MainForm.cs
+++ b/Netch/Forms/MainForm.cs
@@ -414,7 +414,7 @@ namespace Netch.Forms
                 await Task.Run(() =>
                 {
                     NativeMethods.FlushDNSResolverCache();
-                    DNS.Cache.Clear();
+                    DnsUtils.ClearCache();
                 });
 
                 NotifyTip(i18N.Translate("DNS cache cleanup succeeded"));
diff --git a/Netch/Forms/SettingForm.cs b/Netch/Forms/SettingForm.cs
index c368867d..b6ac08c4 100644
--- a/Netch/Forms/SettingForm.cs
+++ b/Netch/Forms/SettingForm.cs
@@ -86,7 +86,7 @@ namespace Netch.Forms
 
             BindCheckBox(ModifySystemDNSCheckBox, b => Global.Settings.ModifySystemDNS = b, Global.Settings.ModifySystemDNS);
 
-            BindTextBox(ModifiedDNSTextBox, s => DNS.TrySplit(s, out _, 2), s => Global.Settings.ModifiedDNS = s, Global.Settings.ModifiedDNS);
+            BindTextBox(ModifiedDNSTextBox, s => DnsUtils.TrySplit(s, out _, 2), s => Global.Settings.ModifiedDNS = s, Global.Settings.ModifiedDNS);
 
             BindCheckBox(RedirectorSSCheckBox, s => Global.Settings.RedirectorSS = s, Global.Settings.RedirectorSS);
 
@@ -116,13 +116,13 @@ namespace Netch.Forms
             BindCheckBox(UseCustomDNSCheckBox, b => { Global.Settings.TUNTAP.UseCustomDNS = b; }, Global.Settings.TUNTAP.UseCustomDNS);
 
             BindTextBox(TUNTAPDNSTextBox,
-                s => !UseCustomDNSCheckBox.Checked || DNS.TrySplit(s, out _, 2),
+                s => !UseCustomDNSCheckBox.Checked || DnsUtils.TrySplit(s, out _, 2),
                 s =>
                 {
                     if (UseCustomDNSCheckBox.Checked)
-                        Global.Settings.TUNTAP.DNS = DNS.Split(s).ToList();
+                        Global.Settings.TUNTAP.DNS = DnsUtils.Split(s).ToList();
                 },
-                DNS.Join(Global.Settings.TUNTAP.DNS));
+                DnsUtils.Join(Global.Settings.TUNTAP.DNS));
 
             BindCheckBox(ProxyDNSCheckBox, b => Global.Settings.TUNTAP.ProxyDNS = b, Global.Settings.TUNTAP.ProxyDNS);
             BindCheckBox(UseFakeDNSCheckBox, b => Global.Settings.TUNTAP.UseFakeDNS = b, Global.Settings.TUNTAP.UseFakeDNS);
@@ -204,7 +204,7 @@ namespace Netch.Forms
         private void TUNTAPUseCustomDNSCheckBox_CheckedChanged(object? sender, EventArgs? e)
         {
             if (UseCustomDNSCheckBox.Checked)
-                TUNTAPDNSTextBox.Text = Global.Settings.TUNTAP.DNS.Any() ? DNS.Join(Global.Settings.TUNTAP.DNS) : "1.1.1.1";
+                TUNTAPDNSTextBox.Text = Global.Settings.TUNTAP.DNS.Any() ? DnsUtils.Join(Global.Settings.TUNTAP.DNS) : "1.1.1.1";
             else
                 TUNTAPDNSTextBox.Text = "AioDNS";
         }
diff --git a/Netch/Models/Server.cs b/Netch/Models/Server.cs
index 79265cf4..320f0295 100644
--- a/Netch/Models/Server.cs
+++ b/Netch/Models/Server.cs
@@ -85,7 +85,7 @@ namespace Netch.Models
         {
             try
             {
-                var destination = DNS.Lookup(Hostname);
+                var destination = DnsUtils.Lookup(Hostname);
                 if (destination == null)
                     return Delay = -2;
 
@@ -122,7 +122,7 @@ namespace Netch.Models
     {
         public static string AutoResolveHostname(this Server server)
         {
-            return Global.Settings.ResolveServerHostname ? DNS.Lookup(server.Hostname)!.ToString() : server.Hostname;
+            return Global.Settings.ResolveServerHostname ? DnsUtils.Lookup(server.Hostname)!.ToString() : server.Hostname;
         }
 
         public static bool Valid(this Server server)
diff --git a/Netch/Utils/DNS.cs b/Netch/Utils/DnsUtils.cs
similarity index 82%
rename from Netch/Utils/DNS.cs
rename to Netch/Utils/DnsUtils.cs
index 7eb0434b..5664da91 100644
--- a/Netch/Utils/DNS.cs
+++ b/Netch/Utils/DnsUtils.cs
@@ -6,12 +6,12 @@ using System.Net;
 
 namespace Netch.Utils
 {
-    public static class DNS
+    public static class DnsUtils
     {
         /// <summary>
         ///     缓存
         /// </summary>
-        public static Hashtable Cache = new();
+        private static readonly Hashtable Cache = new();
 
         /// <summary>
         ///     查询
@@ -42,6 +42,16 @@ namespace Netch.Utils
             }
         }
 
+        /// <summary>
+        ///     查询
+        /// </summary>
+        /// <param name="hostname">主机名</param>
+        /// <returns></returns>
+        public static void ClearCache()
+        {
+            Cache.Clear();
+        }
+
         public static IEnumerable<string> Split(string dns)
         {
             return dns.SplitRemoveEmptyEntriesAndTrimEntries(',');
diff --git a/Netch/Utils/Utils.cs b/Netch/Utils/Utils.cs
index 0ee22a92..786bc7bb 100644
--- a/Netch/Utils/Utils.cs
+++ b/Netch/Utils/Utils.cs
@@ -84,7 +84,7 @@ namespace Netch.Utils
                 }
                 else
                 {
-                    var dnsResult = DNS.Lookup(Hostname);
+                    var dnsResult = DnsUtils.Lookup(Hostname);
 
                     if (dnsResult != null)
                         country = databaseReader.Country(dnsResult).Country.IsoCode;