This paper introduces the improvement culture of Japanese businesses and describes the concept of Kaizen costing calculation. Through the practice of Daihatsu Motor Company, it also explains the specific ways of doing the Kaizen costing, compares the differences between the improvement cost calculation and the standard costing , and points out that kawzen costing fully expresses the continuously improved spirit sought by Kaizen culture of Japanese businesses in the cost management. Kaizen costing is more positive and effective than the standard costing , which is the cost management method deserving to be studied and used by our businesses in China.