Abstract: Cell death is a fundamental phenomenon for organisms to maintain their basic morphology. When a pathogen infects a cell, the process of programmed cell death is activated, the lysed cells carrying the pathogen activate the immune response of the organism in the process of removing infected cells, thus exerting immune defense. The molecular mechanisms of the 4 types of cell death modes apoptosis, pyroptosis, necroptosis and pan-apoptosis as well as their effects on innate immune defense against microbial infections were mainly elaborated in the article, the interactions among the different programmed cell death pathways were briefly interpreted so as to provide new ideas for further study of pathogenic mechanisms of infectious diseases.