Background: Clinical studies have reported that osteoporosis after spinal cord injury (SCI) can be the inflammation-induced base condition and n-3 polyunsaturated fatty acids (PUFAs) suppress the production of pro-inflammatory cytokines. This study documents the effects of n-3 PUFAs on cytokines in a group of patients after chronic SCI. Methods: This double-blind, placebo- controlled trial was designed in 82 (69 males and 13 females) osteoporotic patients with SCI for 4 months. All participants received 1000 mg calcium and 400 IU vitamin D daily. The patients received two MorDHA capsules (435 g of DHA and 65 mg of EPA per day) or two placebo capsules (one with lunch, and the other with dinner) in the treatment and control groups, respectively. Serum interleukins and Dietary intakes were assessed in the beginning and end of the study. Mean difference for each group was compared by using Student′s t test. Results: A total of 75 (13 females, 62 males) participants completed the study over 4 months. The supplemented and control groups did not show any difference in their baseline characteristics. There were significant difference neither between two groups at the end of the study nor in each group between beginning and end of the study. Conclusins: MorDHA supplementation for 4 months had no significant effect on inflammatory markers. Although mean difference in all pro-inflammatory cytokines were not significant in both treatment and control groups during the study (P>0.05), the decrease in treatment group was weakly higher that it may be important in point of clinical view.