Abstract: Applying the Kudo-Weill plagioclase geothermometer to basaltic rocks,the author found that the calculated values are generally higher than the measured ones.This paper offers,an empirical refinement of the Kudo-Weill plagioclase geothermometer based on experimental data of natural basaltic rocks and Ab-An-Di system.Being applied to basaltic rocks or basaltoid rocks of dry system,the refined plagioclase geothermometer can give more realistic and accurate estimates on the crystallization temperature of plagioclases.