With the increasing application of rituximab (RTB) in hematological diseases and autoimmune diseases (AIDs), we have gradually increased our awareness of the adverse reaction of rituximab-associated neutropenia (RAN), but little is known about its true incidence rate, susceptibility risk factors and exact pathogenesis. At present, research groups have conducted a large number of studies on different populations. The team found that age (> 60), advanced disease, systemic lupus erythematosus (SLE) and combined cyclophosphamide therapy were independent risk factors for RAN. However, its exact mechanism is not completely clear. Several hypotheses have been put forward to solve this question, including the production of anti-neutrophil antibodies after RTB, the generation disorder and neutrophil maturation stagnation caused by abnormal B-cell reconstruction, and the amplification of T-large granular lymphocyte population that may induce neutrophil apoptosis. However, there are still many unsolved problems in all aspects of RAN. This article is an update of the incidence rate, risk factors and mechanisms of RAN.