Abstract: Using SPME and GC-MS analysis, the flavor compounds of steamed breads made by sourdoughs collected from Qingdao (SDQ) , Xingtai (HBX) and Zhumadian (HNZ) were detected and the effects of edible alkali on steamed breads flavor profiles were also investigated. The results showed that steamed breads made by sourdoughs from different origins demonstrated unique flavor profiles with compounds including esters, aldehydes and alkenes. The addition of edible alkali decreased both the number of flavor types and the abundance of flavor substances, whereas the major flavor components such as alcohols and aldehydes remained less change. The number of flavor types of SDQ changed from 41 to 39, and the abundance of total substance decreased 30.33%. The number of flavor types of HBX changed from 63 to 60, and the abundance of total substance decreased 28.05%. For sample HNZ, the number of flavor types dropped from 81 to 78, total amuont of substance decreased 21.73%. The abundance of acids and esters decreased significantly after the addition of edible alkali.