Rice is main food crop in Vietnam; it is planted in the whole country with the largest rice area in the Mekong River Delta, and rice cultivation also is the profession of the rural farmers. Rice improvement is an important strategy of the Government and community for food security and rice breeding/selection activities are implemented by the research institutions and event farmers. Participatory plant breeding has been developing in the Mekong River Delta with participation of many farmers. Farmers could select and release the promising rice varieties for using at communities and the six varieties passed all the strict tests and were certified by the MARD. PPB for rice has contributed considerably to seed security, diversity of rice varieties and improvement of rice production in the Mekong River Delta.