RAPD analysis amplified by ten 10- mer random primers including Z2 and Opp17 was used to compare the genetic variations among three mitten crab populations from Skokely in Holland ( Europe) , San Jose of California in United States, and the Yangtze River in China. The results showed ( 1) The Z2700bp band, genet ic identification marker in mitten crab Eriocheir sinensis, can be amplified in both Europe and North America populations. However, the Z2880bp band, genetic identif ication marker in mitten crab Eriocheir Japonica , can not be amplified in these two populartions. It indicated that the mitten crab in Europe, USA, and China were the same species of Eriocheir sinensis but not the Eriocheir japonica; ( 2) The frequency of 947bp band amplif ied by primer Opp17 all reached 100% in above three populations. Combining of results from primer Opp17 with results from primer Z2, it indicated that it is most possible that examined mitten crab populations from Europe and USA were immigrated from the popualtion of the Yangtze River of China.