Impaired wound healing is a well-documented complication in diabetes mellitus. With respect to the mechanism involved in impairment of wound healing in diabetic subjects and also the biological effects of fish oil and ω-3 fatty acids, in this study it was tried to examine whether fish oil-rich diet accelerates wound healing in diabetic rats or not? The adult male rats were divided into six groups. Group I (normal) consisted of normal rats, Group II (control) which received alloxan monohydrate, groups III (fish oil group) and IV (corn oil group or placebo) consisted of rats made diabetic by the alloxan (150 mg/kg s.c.) injection. Groups V and VI consisted of normal rats, which treated with fish oil or corn oil respectively. Groups III and V received 1.6 ml/day of fish oil, and groups IV and VI received 1.6 ml/day of corn oil in the pre- and post-operative days. All animals were wounded by a vertical 4 cm incision in the midline of dorsum. Wound surface area measured at days 0, 2, 5, 10, and 15 of post-operative period. Surface area of the wound in group III was less than group II (p<0.05) and group IV (p<0.05), in all of the post-operative days. Surface area of the wound in group III was the same as group V. Surface-area of the wound in group VI was more than group I (p<0.05). Percentage of wound healing in group III was more than groups II and IV (p<0.05). Healing time was less in group III compared to groups II and IV. These data suggest that fish oil (rich in ω-3 fatty acids), but not corn oil can accelerate wound healing.