Fats are regarded as crucial component of a balanced diet in dog as they help to maintain healthy skin coat, cell structure and function, including vision and learning abilities in addition to enhance taste and palatability of food. Omega-3 fatty acids are polyunsaturated fatty acids which are considered as essential fatty acids in dogs because they cannot be synthesized in the body and hence must be provided in the diet. This paper reviews the potential benefits of omega-3 fatty acids in dogs with osteoarthritis, cardiovascular disorders and renal diseases, atopy, or other inflammatory conditions. In addition, the role of omega fatty acids on neurologic development, behavioral disorders, and reproductive health is summarized along with potential adverse effects like immune function impairment, platelet dysfunction, and altered glucose and lipid metabolism.