diff --git a/disk/disk_windows.go b/disk/disk_windows.go
index 80b1127f6..326bc1f42 100644
--- a/disk/disk_windows.go
+++ b/disk/disk_windows.go
@@ -32,13 +32,6 @@ type Win32_PerfFormattedData struct {
 	AvgDisksecPerRead       uint64
 	AvgDisksecPerWrite      uint64
 }
-type win32_DiskDrive struct {
-	DeviceID     string
-	SerialNumber string
-}
-type win32_DiskPartition struct {
-	DeviceID string
-}
 
 const WaitMSec = 500
 
@@ -164,7 +157,7 @@ func IOCountersWithContext(ctx context.Context, names ...string) (map[string]IOC
 			continue
 		}
 
-		tmpIO := IOCountersStat{
+		ret[d.Name] = IOCountersStat{
 			Name:       d.Name,
 			ReadCount:  uint64(d.AvgDiskReadQueueLength),
 			WriteCount: d.AvgDiskWriteQueueLength,
@@ -173,27 +166,6 @@ func IOCountersWithContext(ctx context.Context, names ...string) (map[string]IOC
 			ReadTime:   d.AvgDisksecPerRead,
 			WriteTime:  d.AvgDisksecPerWrite,
 		}
-		tmpIO.SerialNumber = GetDiskSerialNumber(d.Name)
-		ret[d.Name] = tmpIO
 	}
 	return ret, nil
 }
-
-// return disk serial number(not volume serial number) of given device or empty string on error. Name of device is drive letter, eg. C:
-func GetDiskSerialNumber(name string) string {
-	return GetDiskSerialNumberWithContext(context.Background(), name)
-}
-
-func GetDiskSerialNumberWithContext(ctx context.Context, name string) string {
-	var diskPart []win32_DiskPartition
-	var diskDrive []win32_DiskDrive
-	err := common.WMIQueryWithContext(ctx, "Associators of {Win32_LogicalDisk.DeviceID='"+name+"'} where AssocClass=Win32_LogicalDiskToPartition", &diskPart)
-	if err != nil || len(diskPart) <= 0 {
-		return ""
-	}
-	err = common.WMIQueryWithContext(ctx, "Associators of {Win32_DiskPartition.DeviceID='"+diskPart[0].DeviceID+"'} where AssocClass=Win32_DiskDriveToDiskPartition", &diskDrive)
-	if err != nil || len(diskDrive) <= 0 {
-		return ""
-	}
-	return diskDrive[0].SerialNumber
-}