The reduction of the regular tribute grains from Jiangsu and Zhejiang provinces in the early Tongzhi reign was widely recorded in official documents and local gazetteers． The ensuing reduction of the subsides for sea transportation and transformation of the canal assisting fee ，which was crucial to the reform of the deep-rooted corruption of the tribute grain transportation，had far-reaching influence，however，it can not be found in the Veritable Records nor do modern scholars mention it in their research on the funding of sea transportation． This paper revisits this important issue in the tribute grain transportation of the Qing，reexamines its origins and developments，and explores the subjective and objective causes for the ultimate abolishment of the allowance．