Abstract: Based on local gazetteers and inscriptions on steles, the author surveyed Tian Hou(legendary sea goddess) Temples which were built by the merchant guildhalls in the Qing Dynasty. The temples were widely dispersed over coastal ports, cities and towns in the south, inland, and even overseas. Besides religious belief, merchant guildhalls built Tian Hou Temples to use mazu beliefs to foster cooperation and solidarity among merchants from the same prefecture or profession. Tian Hou Temples were combined with the merchant guildhalls. The temple fairs not only improved relations between merchants of the fuildhalls and inhabitants of the community, but also advanced trade and cultural exchanges in all parts of Qing China. Moreover, by contrasting Qing government and merchant guildhalls constructiong of Tian Hou Temples, the paper shows that businessmen were an important force that promoted the developed and spread of folk belief and folk culture in the Qing Dynasty.