TerminateProcess를 사용해 보십시요.

The TerminateProcess function terminates the specified process and all of its threads.

BOOL TerminateProcess(

    HANDLE hProcess,        // handle to the process
    UINT uExitCode         // exit code for the process  
   );        


Parameters

hProcess

Identifies the process to terminate.
Windows NT: The handle must have PROCESS_TERMINATE access. For more information, see Process Objects.

uExitCode

Specifies the exit code for the process and for all threads terminated as a result of this call. Use the GetExitCodeProcess function to retrieve the process's exit value. Use the GetExitCodeThread function to retrieve a thread's exit value.

Return Values

If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero. To get extended error information, call GetLastError.