To assess and compare autoimmune activity in patients with premature ovarian failure (POF) and menopause. Method: Thirteen women with premature ovarian failure but with no history of autoimmune disease were recruited into the study group and 15 women with natural menopause into control group between January 1999 and November 2000. The mean FSH levels of patients with premature ovarian failure were 73.95±29.11 (range: 41-130.7 U/L). Nuclear (antinuclear antibody=ANA, double-stranded DNA antibody=antidsDNA) and cardiolipin antibodies (IgM, IgG), immunoglobulins (IgM, IgG, IgA) and complement (C3, C4) levels were determined. Students t test was used to compare the groups. Results: Antinuclear antibody was positive in 30.7% of patients with premature ovarian failure and in 13.3% of controls. There was no significant difference in anticardiolipin antibodies, immunoglobulins and complement levels between the groups (p>0.05). Conclusion: In our study, no autoimmune deficiency was found in patients with POF.Keywords: Premature ovarian failure, autoimmunity and menopause.