Objective: The present study has been designed to evaluate the histological effects of the daily consumption of omega-3 on submandibular salivary gland of old rats. Material & methods: Forty old white male rats (12-15 month age old), weighing 300 to 350gs, were used in this study. The rats were divided into two groups (20 rats/each). Control group where rats did not receive any dietary supplement. Experimental group where rats received omega-3 (60 mg/Kg) twice daily for three months through intra- gastric intubation. All rats were sacrificed after three months. Soft tissue specimens were obtained from submandibular salivary gland of the rats in all the studied groups. The sections were examined histologically and ultra-structurally. Results: Histopathological changes observed in control group included; distortion and decrease in the overall size of the acini and granular convoluted tubules increase in the amount of fatty tissue, fibrous tissue and inflammatory cell infiltration. In experimental group, the acini and ducts appeared nearly normal and there was marked decrease in the inflammatory cell infiltration. Electron microscopic examination of the control group revealed cytoplasmic vacuolization in acini and ducts, degenerated organelles and pyknotic nuclei. In experimental group, the acini and ducts appeared nearly normal in size, shape and structure. Conclusion: Omega-3 showed significant improvement in many age related changes of submandibular salivary gland.Key words: Omega-3, Aging, Submandibular salivary gland.