Abstract: This article reports the determination of cell mediated immunity function with LTT, EtRFCT, EaRFCT end PHA-skin test in SLE. A variable degree of lowering of T lymphocytes function was revealed, Among those tests EaRFCT and,LTT were considered to be more active to reflect the cell mediated immuaity. Determination of humoral immunity showed elevation of IgG in 48% cases. The antinuclear antibodies were positive, in 81.1% cases, and the accumulated positive rate was 99.3%. The titer of antinuclear antibodies above o equal to 1:80 was observed more often in activr cases. The commonest fluorescent nuclear pattern observed was speckled type. Peripheral, speckle-e thready and homogenous types were observed more often in active cases. In patients of lupus nephritis with albuminuria, the determination of. urinary antinuclear antibodies was positive in 41.7% cases. In lupus patients with involvement of central nervous system, the determination of antinuclear antibodies in cerebral spinal fluid was positive in 70% cases. The detection of serum anti-dsDNA with indirect hemagglutination test was positive in 29.89% cases. The result was basically parallel with isotopic method, The patients of positive group had relatively shorter duration of illness and higher incidence of renal involvement. The detection of circulatory immuno-complex with polyethylene glycol precipitation method was elevated in 43% cases. Through dissociation test, the main content of immuno-complex. was found to be nuclear antigen and antinuclear antibody complex. The measurement of blood CH₅₀ and C₃ showed lowering in a variable degree. Finally the authors discussed the pathogenesis of SLE from these abnormal immunologic studies.