Aiming to improve the indoor thermal comfort of residential buildings in Jiangnan region locating in the south bank of Middle – Lower Yangtze River of China, this paper presents the work of bioclimatic analysis by using the software Climate Consultant 5.4 for the city of Shanghai, Hangzhou and Quzhou which were selected to represent three sub-areas of Jiangnan region (the plain area beside the Tai Lake, the inner plain area and the mountainous area) defined by the author. The results of bioclimatic analysis show that the most effective five strategies for improve indoor thermal comfort of this region include sun shading of windows (SSW), adaptive comfort ventilation (ACV), fan-forced ventilation cooling (FVC), internal heat gain (IHG) and passive solar heating (PSD). Based on the work of field observation, the bioclimatic feature of the traditional dwelling in this region were summarized qualitatively, and the three strategies including natural ventilation, sun shading and passive solar heating were validated as the best passive design strategies for this region. Furthermore, the effectiveness of four indoor environmental control strategies including ACV, FVC, IHG and PSD were derived in terms of all year, seasonal and monthly assessment.