Water samples from rivers (150), running water (40), waste water (12), food (41) were analyzed to detect the presence of V cholerae. Result: The result showed proofs of cholera transmission through border: temporal relationship (Kampuchean provinces bodering with An Giang occurred cholera since December 2009), Kampuchean cholera patients came to An Phu district hospital to get treatment 2 weeks before the first Vietnamese cholera case.