Abstract: Gene flow is one of the important environmental risks of transgenic crops. China is one of the most important country with cultivated soybeans and wild soybeans. Furthermore, the distribution area of cultivated soybean and that of wild soybean highly overlap in China. Therefore, strict evaluation and researches on gene flow from transgenic soybean to cultivated soybeans and wild soybeans must be conducted before the commercial cultivation of transgenic soybeans in China. In Yitong County, Jilin Province, transgenic EPSPS+PAT soybean S4003.14, developed by local organization, was studied on its gene flow to 5 cultivated soybeans and 5 wild soybeans. The results show that the flowering overlaps of S4003.14 and the 5 non-transgenic soybeans were 17-27 days, and that of S4003.14 and 5 wild soybean lines were 19-23 days. Under the intercropping condition, as the results of gene flow, the outcrossing rates of transgenic EPSPS+PAT soybean S4003.14 to the 5 non-transgenic soybeans and to the 5 wild soybeans were 0.16%-0.93% and 0.06%-0.19%, respectively. The fertility of the hybrid offsprings was normal. No gene flow was detected when the distance between S4003.14 soybean and non-transgenic cultivated soybeans was more than 1 m.