Sera from 42 antinuclear antibodies (ANA) positive systemic lupus erythematosus (SLE) patients, 33 rheumatoid arthritis patients (patients control) and 31 apparently healthy persons (healthy control) were tested for antibodies to double stranded DNA (ds DNA) using commercial RIA kit and human metaphase chromosomes fluorescence (M.P.), haemagglutination (H.A.) and dot blot ELISA (D.B) assays (locally prepared kits). A comparison of these four assays was done and chi square test revealed no significant difference among the four tests (M.P, H.A/ D.B and RIA) at 5% level (P>0.05). The correlation coefficients among the efficiencies of different tests (Metaphase, Haemagglutination, dot blot) and RIA were in all cases about intermediate correlation (r=Q.523-0.716) and the highest correlation coefficient was between RIA and Metaphase assay which was about 0.716. Sera from the 21 RIA positive SLE patients (out of the 42 SLE patients) and 31 normal persons, were tested for Abs to ds DNA using M.P, H.A, and D.B. assays and the results pf ,these tes.ts were used to measure the sensitivity and specificity of these tests, which revealed that the most sensitive test is the Metaphase assay (95%) followed by H.A. (85%) then D:.B. (81:%) while,the most specific test was the M.P. (90.3%) then D.B. and H . A. ,77 .4% each . Our study clearly demonstrates thatT.vaginalis can not be used as a substrate for IFT for detection anti ds DNA Abs and IFT using human M.P. chromosome correlates well with results of more established tests for anti ds DNA Abs i.e, RIA, so M.P assay offers an economic and reliable alternative to the isotope technique for the detection of anti ds DNA Abs in sera of SLE patients and its related disease states, for the clinical laboratory. Therefore, we recommend its routine use in detection of anti ds DNA Abs. Although H.A. & D.B. are neither specific nor (sensitive for the diagnosis of SLE, yet it may have some practical application as a fast screening test in areas where J'FT-facilities are not available.