Macroautophagy(hereafter autophagy)is a catabolic process by which autophagosomes arising from an isolation membrane fuse with lysosomes to degrade components in the cytoplasm.Autophagosome-lysosome fusion step is one of the key steps during the process of macroautophagy.The step is extremely complicated and its detailed mechanisms remain unclear.It consists of two phases:first phase is autophagosome migration phase and second phase is fusion of autophagosomes and lysosomes phase.Recently,various molecules have been reported to be involved in each phase.In the first phase,mi-crotubules and actin remodeling mechanism are involved.In the second phase,soluble N-ethyl-maleimide-sensitive factor attachment protein receptor(SNARE)proteins,Rab family proteins,phosphoinositide 3-kinase(PI3K)complex and Rubicon are involved.In the present review,we introduce recent findings related to autophagosome-lysosome fusion step and discuss liver diseases possibly associated with autophagosome-lysosome fusion dysfunction.