diff --git a/PcAtChipsetPkg/Library/AcpiTimerLib/AcpiTimerLib.c b/PcAtChipsetPkg/Library/AcpiTimerLib/AcpiTimerLib.c
index 7dc11014a5..0a49093dbf 100644
--- a/PcAtChipsetPkg/Library/AcpiTimerLib/AcpiTimerLib.c
+++ b/PcAtChipsetPkg/Library/AcpiTimerLib/AcpiTimerLib.c
@@ -59,7 +59,7 @@ AcpiTimerLibConstructor (
 
   //
   // If the register offset to the BAR for the ACPI I/O Port Base Address is 0x0000, then
-  // no PCI register programming is required to enable access to the the ACPI registers
+  // no PCI register programming is required to enable access to the ACPI registers
   // specified by PcdAcpiIoPortBaseAddress
   //
   if (PcdGet16 (PcdAcpiIoPciBarRegisterOffset) == 0x0000) {
diff --git a/PcAtChipsetPkg/Library/SerialIoLib/SerialPortLib.c b/PcAtChipsetPkg/Library/SerialIoLib/SerialPortLib.c
index 25c4cefc13..aa5657a7fd 100644
--- a/PcAtChipsetPkg/Library/SerialIoLib/SerialPortLib.c
+++ b/PcAtChipsetPkg/Library/SerialIoLib/SerialPortLib.c
@@ -58,7 +58,7 @@ UINT8   gBreakSet = 0;
   If the serial device could not be initialized, then return RETURN_DEVICE_ERROR.
 
   @retval RETURN_SUCCESS        The serial device was initialized.
-  @retval RETURN_DEVICE_ERROR   The serail device could not be initialized.
+  @retval RETURN_DEVICE_ERROR   The serial device could not be initialized.
 
 **/
 RETURN_STATUS
@@ -139,7 +139,7 @@ SerialPortWrite (
 
   while ((NumberOfBytes--) != 0) {
     //
-    // Wait for the serail port to be ready.
+    // Wait for the serial port to be ready.
     //
     do {
       Data = IoRead8 ((UINT16) gUartBase + LSR_OFFSET);
@@ -180,7 +180,7 @@ SerialPortRead (
 
   while ((NumberOfBytes--) != 0) {
     //
-    // Wait for the serail port to be ready.
+    // Wait for the serial port to be ready.
     //
     do {
       Data = IoRead8 ((UINT16) gUartBase + LSR_OFFSET);