The invention relates to a domestic sewage treatment device which comprises eight relatively independent reaction units of an anaerobic tank, a facultative tank, a primary aerobic fluidization tank, asecondary aerobic fluidization tank, an aerobic illumination phycomycete symbiosis fluidization tank, a primary aerobic ecological tank, a secondary aerobic ecological tank and an ecological sedimentation tank, wherein the eight reaction units are in serial connection. Or some reaction unit except the ecological sedimentation tank can be repeatedly arranged according to need to be in serial connection to form a reactor more than eight levels. The sewage treatment device disclosed by the technical scheme of the invention has a biological-ecological synergistic technical effect in effectively treating and reusing domestic sewage on site.