Objective: Determination of whether serum resistin in lean rheumatoid arthritis patients correlates with disease activity and radiological joint damage or not. Subjects and Methods: 75 subjects were included; 25 patients diagnosed with active rheumatoid arthritis (RA), 25 patients with inactive RA, and 25 healthy individuals served as control. All were subjected to history taking, clinical examination, routine laboratory investigations and determination of serum resistin level. Plain X-ray of both hands and feet for RA patients and assessed according to Larsen score. Results: There was a significant increase in serum resistin level in active RA when compared to inactive RA and controls. Resistin also showed a significant positive correlation with DAS 28 score, ESR, CRP, RF, anti CCP, TC, TG, LDL, but the correlation with Larsen score was not significant. Conclusion: There is association between serum resistin level and disease activity, suggesting that it may be useful in evaluating RA disease activity.