<b>Antecedents of Functional Food Purchase Intention of Sri Lankan Consumers The Mediating Effect of Consumer Attitudes</b> “Functional Food” is food and food components which provide benefits beyond basic nutrition, and it includes a wide variety of food and food components believed to improve overall health and well being of people which help to reduce the risk of specific diseases. This paper examines antecedents Customer knowledge, Necessity, Safety, Confidence, Rewards of functional food purchase intention of Sri Lankan consumers and the mediating effect of consumer attitudes. Since the underlying attitudes of humans cater to their behaviour, it is important for marketers to understand the attitudes in relation to functional food so that they could be properly used in implementing marketing strategies. Objectives included examining the impact of customer knowledge, necessity, safety, confidence of functional and rewards from functional food on the purchase intention and the mediating impact of consumer attitude towards functional food on the relationship between the antecedents and purchase intention. The sample consists of 280 respondents from Colombo district within the age group of eighteen to sixty. Data were analyzed using correlation and regression to test hypothesis and it revealed that customer knowledge, necessity and safety has a negative impact while confidence and rewards has a positive impact on the purchase intention of functional food. A full mediation by consumer attitudes on the impact from customer knowledge and partial mediation on the impact from necessity, safety, confidence and rewards on the purchase intention could be observed. These findings will provide food companies and policy planners with valuable insights on consumer behaviour. Functional food, Attitudes, Mediating effect 50-56 Issue-3 Volume-5 R. M. K. S. Rasanjalee