This dissertation reports the results from an empirical research of factors that influence and moderate the foreign entry mode decision from institutional perspective. To explain the considerably uneven proportions of joint venture and wholly-owned subsidiary in different regions in emerging countries such as China, this study focuses on national formal institution (national regulation) and specific regional informal institutions (regional corruption and regional ethnicity), and explores the moderation effect of regional informal institutions on the relationship between the national formal institution and the entry mode decision. The results of this study show that regional informal institutions not only directly influence the entry mode choice, but also moderate the relationship between the national formal institutions and the foreign entry mode choice.