diff --git a/SourceLevelDebugPkg/Library/DebugAgent/DebugAgentCommon/DebugTimer.c b/SourceLevelDebugPkg/Library/DebugAgent/DebugAgentCommon/DebugTimer.c
index e287c4cbbe..d01d1ae484 100644
--- a/SourceLevelDebugPkg/Library/DebugAgent/DebugAgentCommon/DebugTimer.c
+++ b/SourceLevelDebugPkg/Library/DebugAgent/DebugAgentCommon/DebugTimer.c
@@ -32,6 +32,7 @@ InitializeDebugTimer (
   UINT32      InitialCount;
   UINT32      ApicTimerFrequency;
 
+  InitializeLocalApicSoftwareEnable (TRUE);
   GetApicTimerState (&ApicTimerDivisor, NULL, NULL);
   ApicTimerFrequency = PcdGet32(PcdFSBClock) / (UINT32)ApicTimerDivisor;
   //
diff --git a/SourceLevelDebugPkg/Library/DebugAgent/DxeDebugAgent/DxeDebugAgentLib.c b/SourceLevelDebugPkg/Library/DebugAgent/DxeDebugAgent/DxeDebugAgentLib.c
index 35fb5e6450..a63932c6a7 100644
--- a/SourceLevelDebugPkg/Library/DebugAgent/DxeDebugAgent/DxeDebugAgentLib.c
+++ b/SourceLevelDebugPkg/Library/DebugAgent/DxeDebugAgent/DxeDebugAgentLib.c
@@ -372,6 +372,7 @@ InitializeDebugAgent (
     //
     // Check if CPU APIC Timer is working, otherwise initialize it.
     //
+    InitializeLocalApicSoftwareEnable (TRUE);
     GetApicTimerState (NULL, &PeriodicMode, NULL);
     TimerCycle = GetApicTimerInitCount ();
     if (!PeriodicMode || TimerCycle == 0) {
diff --git a/SourceLevelDebugPkg/Library/DebugAgent/SmmDebugAgent/SmmDebugAgentLib.c b/SourceLevelDebugPkg/Library/DebugAgent/SmmDebugAgent/SmmDebugAgentLib.c
index 3a759f900d..32b1ae6c8f 100644
--- a/SourceLevelDebugPkg/Library/DebugAgent/SmmDebugAgent/SmmDebugAgentLib.c
+++ b/SourceLevelDebugPkg/Library/DebugAgent/SmmDebugAgent/SmmDebugAgentLib.c
@@ -280,6 +280,7 @@ InitializeDebugAgent (
     //
     // Check if CPU APIC Timer is working, otherwise initialize it.
     //
+    InitializeLocalApicSoftwareEnable (TRUE);
     GetApicTimerState (NULL, &PeriodicMode, NULL);
     TimerCycle = GetApicTimerInitCount ();
     if (!PeriodicMode || TimerCycle == 0) {