Contents of nutritional components in seed cake of Jatropha curcas Linn. before and after detoxification by hydrogen peroxide were determined and compared. The results show that phorbol esters is not existed in seed cake of J. curcas after detoxification. Contents of water, crude protein, crude fiber, reducing sugar and total sugar in seed cake after detoxification all are lower than those before detoxification, contents of different fatty acids and amino acids in seed cake after detoxification increase or decrease, but there is no significant difference (P>0. 05). It is suggested that detoxified seed cake of J. curcas can be further developed for using as plant protein feed.