Abstract: After obtaining the department relationship table by the method of classical systematic layout planning(SLP), this paper adapts a genetic algorithm to find out the suitable plant layouts. The proposed method, combining SLP and the genetic algorithm, can derive visual acceptable results quite efficiently and offsets some disadvantages of traditional SLP such as the uncertainty of results, time consuming, and easy influence by human perception. A practical application of the improved SLP method is discussed in a manufactory producing hydraulic steering control units. The effectiveness and sensitivity of the proposed method for plant layout problems in moderate scales are analyzed.