Considerable clinical and experimental evidence now supports the idea that deficiencies or imbalances in certain highly unsaturated fatty acids may contribute to a range of common developmental disorders, including attention deficit hyperactivity disorder (ADHD). The few intervention studies with long-chain polyunsaturated fatty acid supplementation have reported inconsistent and marginal results. This pilot study evaluates the effect of alpha-linolenic acid (ALA)-rich nutritional supplementation in the form of flax oil and antioxidant emulsion on blood fatty acid composition and behaviour in children with ADHD. Post-supplementation levels of red blood cell membrane fatty acids were significantly higher than pre-treatment levels as well as the levels in control. There was significant improvement in the symptoms of ADHD reflected by reduction in total hyperactivity scores of ADHD children derived from ADHD rating scale.