Hà Tiên was established by a small group of Chinese people mostly men who supported the Ming Dynasty and were opposed to the Qing Dynasty, led by Mo Jiu (Mạc Cửu). When they arrived in Đàng Trong (as southern Vietnam was called while under the rule of the Nguyễn lords), the Nguyễn Lords ordered the king of the Khmer (then a vassal state of Đàng Trong) to grant land to these Chinese people. These people built markets in this place and turned it into a busy business town. Vietnamese people gradually arrived here. This town later was merged into Vietnamese territory when Mo Jiu delivered its sovereignty to the Nguyễn Lords. Mo Jiu was then conferred the position of ruler of this town.
Ha Tien is the site of a large cement plant. Its history goes back to the Republic of Vietnam (South Vietnam), where it was one of the largest industrial projects when construction was started in April 1961.