In this paper 15 genotype peppers with different pungency are used to detect the content of capsaicin and dihydrocapsaicin during the course of the development of pepper fruits,and classified based on pungency.The results showed that the content of capsaicin and dihydrocapsaicin increased firstly,then decreased during pepper fruit development.Among 15 pepper varieties,India pepper has the highest content of capsaicin and dihydrocapsaicin and is the most pungent with 932000 SHU.The content of capsaicin and dihydrocapsaicin reach 6.21 mg · g-1,2.55 mg · g-1 respect in Huangdenglong Pepper from Hainan which was second pungent pepper and most pungent pepper in the researched Chinese varieties.Above two species of pepper belong to most pungent pepper but small pepper and Chaotianjiao belongs high pungent pepper.Furthermore no capsaicin and dihydrocapsaicin were detected in sweet pepper.This experiment attempts to establish the relationship of SHU and pungency degree.