Abstract: Traditional process design of cotton mill is conducted manually.Due to a variety of processes and all sorts of equipment,the process design has the disadvantages of high workload and low efficiency.A high-efficiency and practical computer-aided process design system for cotton mill is developed.Its logical model is established by means of data flow diagram,and the physical model is designed on the basis of the features of actual data processing.This system has an integrated function,which involves choice of process flow,calculation of process,choice of machine model,allocation and layout of equipment,analysis of technical and economical values,and management of files and documents.