多线程处理串口的倒是没有，DEMO代码倒是有,你搜下 ThreadPool.QueueUserWorkItem 这个东西吧

var doEvents = new ManualResetEvent[threadCount];
                for (var i = 0; i < threadCount; i++)
                {
                    doEvents[i] = new ManualResetEvent(false);
                    ThreadPool.QueueUserWorkItem(new WaitCallback(DealData), new object[] { i, doEvents[i] });
                }
                WaitHandle.WaitAll(doEvents);

public void DealData(object eventParams)         {           

var threadId = (int)(((object[])eventParams)[0]);      //当前线程ID            

var doEvent = (ManualResetEvent)(((object[])eventParams)[1]);            

var perThreadCount = dataTable.Rows.Count / threadCount;       //平均每个线程处理数据

            for (int i = 0; i < dataTable.Rows.Count; i++)             {               

　　　　　　if (i < (threadId) * perThreadCount)           continue;

                if ((i >= (threadId + 1) * perThreadCount) && threadId != (threadCount - 1))                break;

                ImportData(dataTable.Rows[i]);            

}            

doEvent.Set();       

}