Vietnam is divided into 58 provinces (Vietnamese: tỉnh) and 5 municipalities existing at the same level as provinces (thành phố trực thuộc trung ương). The provinces are divided into districts (huyện), provincial cities (thành phố trực thuộc tỉnh), and district-level towns (thị xã), which are subdivided into commune-level towns (thị trấn) or communes (xã). The municipalities are divided into rural districts (huyện) and urban districts (quận), which are subdivided into wards (phường).
More information, including a list of provinces, on the Wikipedia page [1]