Under the background of energy saving and emission reduction, the application of supercritical fluid microcellular injection foaming products was of great significance to realize the lightweight of traffic vehicles. The control of cellular morphology in supercritical fluid microcellular injection molding process was pivotal for product quality control but difficult to achieve. Therefore, the reason of heterogeneous cell morphology was analyzed according to the process of microcellular injection foaming. Secondly, the process parameters, material modification, process method improvement and technologies of assist foaming were reviewed, and the corresponding cell morphology control mechanism was summarized either. Finally, the development direction of microcellular injection molding based on supercritical fluid was prospected.