It is undeniable that convenience stores have expanded rapidly in the Vietnam retail market in recent years [1]. Convenience store chains such as Circle K, 7-Eleven, VinMart and B's Mart have been popular grocery shopping destinations for shoppers in Vietnam due to the busy modern life and the restricted time for shopping. Noticeably, Millennials with the tremendous spending power have become an important shopper group of the convenience store. This research goes to find out the Millennials' buying behaviour and the influential levels of factors including convenience, store layout, price and technology on different Millennial groups in this market.