Plant litter is the main organic material and energy source for soil fauna and microorganisms. Litter types, composition, and physico-chemical properties influence the quality of soil organic matter. In this review, we examined the relationship between the types, quality, physical properties, layer effects, priming effects, carbon deposition in the rhizosphere of plant litter and the decomposition of soil organic matter. This review provides a theoretical basis for the study of the effects of plant litter on soil organic matter. We suggest that the effects of plant litter decomposition on the soil micro-organisms and enzyme activities need to be further explored in the context of global warming.