Abstract: An investigation on thermal comfort of multitude in the environments without air-conditioning in Jiangsu and Zhejiang provinces was conducted in the summer, 2000 and 2001. The environments investigated are outside the American Society of Heating Refrigerating and Air Conditing Engineerings（ASHRAE） comfort zone. The results showed that the actual mean thermal sensation is lower than predicted mean vote (V_pm), about 0.64 V_pm, and the upper limits of ET^*（t_e） acceptable by 80% of people is about 30 ℃, much higher than 26 ℃ recommended by the current ASHRAE standard. These facts reveal that people in those areas have adapted to such a climate and can endure heat in a certain degree, and verify that adaptation to the indoor environment may change human expectations and thermal sensations. Proper amendments to the current standard should be given according to actual conditions.