PLC是以微处理器为核心的工业控制装置。在工业控制中,常常需要对PLC所采集的数据和工作状态进行监测控制,Visual C++是一种Windows应用程序开发工具,在图形处理和数据库管理等方面具有较强的功能,用它来实现底层的通信控制有着更快的速度。本文旨在探讨用可视化编程语言VisualC++实现计算机与PLC之间的串行通讯技术,充分合理地利用系统资源及特点,提高通讯效率。-PLC is a microprocessor as the core of industrial control devices. In industrial control, often by the need for PLC data acquisition and monitoring the work of state control, Visual C++ Is a Windows application development tools, graphics processing and database management has a strong feature, use it to achieve the underlying communication control has a faster rate. This paper aims to explore visual programming language VisualC++ Achieve between computer and PLC serial communication technology, and fully rational use of system resources and features to enhance communication efficiency.