Abstract: Investigations showed that wild soybean grew in a vast area from about 24°N (middle-northern Guangdong Province and Guangxi Zhuang Autonomous Regions) in the south to 53 ° N (Heilongjiang River valley) in the northern China, and that there was no wild soybean to find in three regions Xinjiang, Qinghai and Hainan. The area of 30 to 45 ° N was a diverse region of the wild soybean in China, where the wild soybean has an extensive distribution, large populations and rich types. The highest point of wild soybean distribution in China was 2670 m, locating at 27° 30` N, Ninglang County, Yunnan Province. Two critical meteorological indexes related temperature and humidity was key factors to influence the distribution of wild soybean in China: no wild soybeans were found in the areas having a monthly mean temperature of below 20 °C in the warmest months or lasting seven months and over of more than 20 °C monthly mean temperature, and having an annual precipitation of less than 300 mm during a year.