Abstract: The systematic classify of Cobombaceae is summarized. The fossils and modern distributional pattern are discussed, the climates during gla-ciers was the main factors affected it. In the light of the recurtheory to deduce the origen of Brasenia schreberi from morphological features of it's seedling, the ancestor would be the palaeoplant of Ranunculaceae by infe-rence. In addation, the ryhthm of flowers sink when nght and emerge when daytimes is studied. The struture and ecological adaptation of winterbud as well as the character and function of the colloid are probed into.