Based on the introduction of the principle of numerical control transformation for horizontal lathes feed mechanism economically, the whole structure of CAD system on numerical control transformation for horizontal lathes feed mechanism is proposed. Its main steps, flow chart and technical features are discussed. 在介绍卧式车床进给机构经济型数控改造原理的基础上,提出卧式车床进给机构数控改造计算机辅助设计系统的总体结构,讨论了系统设计的主要步骤流程和技术特点。