Due to the perniciousness and universality of the submarine landslide, it has been attracting increasing attention in the world as a hot issue. In order to deepen the understanding of the submarine landslide, the classification of categories and the genetic mechanism were discussed by systematically analyzing the domestic and international research results, meanwhile, the trigger mechanisms about the hydraulic forces and gas hydrate dissociation were emphatically analyzesd. It is showed that the classification of categories is getting more and more deepening, detailed and generalized. The formation of submarine landslide is the outcome of internal and external causes, and its genetic mechanism is extremely complicated. The research direction and working emphasis were pointed out: developing in-situ real time monitoring technique; establishing database about submarine landslide and consummating physical and numerical model.