WSH has no function or method for retrieving a script’s path, so in VBScript you can use the ScriptFullName property of the WScript object to extract the path, as shown here:

Function GetPath
    ' Retrieve path to the script file.
    Dim path
    path = WScript.ScriptFullName  ' Script filename
    GetPath = Left(path, InStrRev(path, "\"))
End Function

This function assumes that the path ends with a backslash character. But as long as Microsoft implements GetParentFolderName correctly, you get the path more portably with:

Dim fso
Set fso = CreateObject("Scripting.FileSystemObject")
Path = fso.GetParentFolderName(WScript.ScriptFullName)

From Windows Script Host 2.0 Developer’s Guide by Gunter Born.