Abstract
This paper is to cover brief history of the development of LWR fuel performance analysis codes in Japan. This includes the FEMAXI-III code which calculates local stress and strain of the cladding at power ramp due to the pellet cladding mechanical interaction (PCMI) using axisymmetric finite element method. From this code some improved codes were developed, such as FEMAXI IV, IRON and EIMUS. The FEMAXI-IV is developed by J AERI to add capacity of transient analysis and che IRON code was developed by Shikoku Electric Power Co. to analyze fuel reliability at load following operation and the EIMUS code was developed by CRIEPI for high burnup analysis. The major objective and contents of adapted submodels in these codes are presented with some calculational results. The future development and utilization of the codes, especially for performance analyses at high burnup, will be briefly discussed.