The ichthyosaurs, a major group of maine reptile of Mesozic ear, it form like the shark or dolphin. Recently, we discovered four gravid specimens of Qianichthyosaurus and Shastsaurids from the Last Triassic of Guanling, Guizhou of China. These exquisitely preserved ichtyosaur specimens provide the unequivocal new evidence of vovoviparaity of reproductive mode.[