The complement system is a part of the innate immune system, playing an important role in protecting hosts from pathogens.Many researches showed that complements were strongly associated with a wide spectrum of glomerulonephritis, such as IgA nephropathy, membranous nephropathy, post infectious glomerulonephritis, membranoproliferative glomerulonephritis, C₃ nephropathy, focal segmental glomerulosclerosis, lupus nephritis, and ANCA induced renal vasculitis.Various factors may induce abnormal activation or dysregulation of the local or systemic complement system, resulting in further kidney injury.Selective blocking of the complement cascades could protect the kidney.Further investigations are needed to fully understand the mechanism of complement, and targeting complement could be considered a novel therapeutic method in refractory renal diseases.