SiChuan dishes developped quickly in Tang and Song Dynasties and had already been famous in Ming and Qing Dynasties. Now they are already through all over the world. They characterise as sour,sweet,peppery,and heavy flavour. SiChuan Dishes are liked not only by SiChuan people,but other places of China,even many foreigh countries. Mapo tofu is one of the reprentative dishes of them.