diff --git a/src/PSProxmoxVE/Cmdlets/HA/SetPveHaRuleCmdlet.cs b/src/PSProxmoxVE/Cmdlets/HA/SetPveHaRuleCmdlet.cs
index bb1d1d9..89d7e87 100644
--- a/src/PSProxmoxVE/Cmdlets/HA/SetPveHaRuleCmdlet.cs
+++ b/src/PSProxmoxVE/Cmdlets/HA/SetPveHaRuleCmdlet.cs
@@ -19,6 +19,11 @@ namespace PSProxmoxVE.Cmdlets.HA
             HelpMessage = "HA rule ID.")]
         public string Rule { get; set; } = string.Empty;
 
+        /// <summary>Rule type (required by PVE API on update).</summary>
+        [Parameter(Mandatory = true, Position = 1, HelpMessage = "HA rule type: node-affinity or resource-affinity.")]
+        [ValidateSet("node-affinity", "resource-affinity")]
+        public string Type { get; set; } = string.Empty;
+
         /// <summary>Rule state.</summary>
         [Parameter(Mandatory = false, HelpMessage = "Rule state: enabled or disabled.")]
         [ValidateSet("enabled", "disabled")]
@@ -42,7 +47,7 @@ namespace PSProxmoxVE.Cmdlets.HA
 
             var service = new HaService();
 
-            var data = new Dictionary<string, string>();
+            var data = new Dictionary<string, string> { ["type"] = Type };
             if (State != null) data["state"] = State;
             if (Comment != null) data["comment"] = Comment;
             if (Properties != null)
diff --git a/tests/PSProxmoxVE.Tests/HA/HaCmdlets.Tests.ps1 b/tests/PSProxmoxVE.Tests/HA/HaCmdlets.Tests.ps1
index 96fea4f..501cbf9 100644
--- a/tests/PSProxmoxVE.Tests/HA/HaCmdlets.Tests.ps1
+++ b/tests/PSProxmoxVE.Tests/HA/HaCmdlets.Tests.ps1
@@ -736,6 +736,15 @@ Describe 'Set-PveHaRule' -Tag 'Unit' {
             $isMandatory = $p.ParameterSets.Values | Where-Object { $_.IsMandatory }
             $isMandatory | Should -Not -BeNullOrEmpty
         }
+        It 'Should have mandatory Type parameter with ValidateSet' {
+            Skip-IfMissing 'Set-PveHaRule'
+            $p = $script:Cmd.Parameters['Type']
+            $p | Should -Not -BeNullOrEmpty
+            $isMandatory = $p.ParameterSets.Values | Where-Object { $_.IsMandatory }
+            $isMandatory | Should -Not -BeNullOrEmpty
+            $vsAttr = $p.Attributes | Where-Object { $_ -is [System.Management.Automation.ValidateSetAttribute] }
+            $vsAttr | Should -Not -BeNullOrEmpty
+        }
         It 'Should have optional State parameter with ValidateSet' {
             Skip-IfMissing 'Set-PveHaRule'
             $p = $script:Cmd.Parameters['State']
@@ -762,7 +771,7 @@ Describe 'Set-PveHaRule' -Tag 'Unit' {
     Context 'Without active session' {
         It 'Should throw when no session is active' {
             Skip-IfMissing 'Set-PveHaRule'
-            { Set-PveHaRule -Rule 'rule1' -ErrorAction Stop -Confirm:$false } |
+            { Set-PveHaRule -Rule 'rule1' -Type 'node-affinity' -ErrorAction Stop -Confirm:$false } |
                 Should -Throw '*No active Proxmox VE session*'
         }
     }
diff --git a/tests/PSProxmoxVE.Tests/Integration/16_Cluster.Tests.ps1 b/tests/PSProxmoxVE.Tests/Integration/16_Cluster.Tests.ps1
index e66e669..405ccc7 100644
--- a/tests/PSProxmoxVE.Tests/Integration/16_Cluster.Tests.ps1
+++ b/tests/PSProxmoxVE.Tests/Integration/16_Cluster.Tests.ps1
@@ -360,7 +360,7 @@ Describe 'Cluster Config & HA Lifecycle — Integration' -Tag 'Integration' {
                 return
             }
 
-            { Set-PveHaRule -Rule 'pester-rule-1' `
+            { Set-PveHaRule -Rule 'pester-rule-1' -Type 'node-affinity' `
                 -Comment 'Updated by Pester' `
                 -Confirm:$false `
                 -ErrorAction Stop } | Should -Not -Throw