Since 2004, the French fishery field has had to cope with a levelling off of consumption of fresh seafood products whereas the consumption of processed seafood products is increasing. Nowadays, consumers prefer easier products: fresh deli products, easy to cook or ready to consume. Therefore, fresh seafood products do not seem to fulfil current consumer demand intrinsically (aspect, taste) and extrinsically (cooking methods, use, origin, brand and price). In order to understand the evolution of consumers’ needs (attitude and perception), several behavioural studies have been conducted within the COGEPECHE research programme. In our article, we focus only on cognitive dissonance analysis. Four other analysis methods have been carried out: focus group, trade off, cognitive chains and Delphi method. The cognitive dissonance concept has been elaborated by Léon Festinger in 1957 (principle of congruity). The aim of this method is to collect consumers’ believes (product attributes) and opinions (buying intention). We tried to collect and group the elements inciting cognitive dissonance behaviour during the buying process. We interviewed 168 consumers of fresh seafood products using the quota method. Four representatives’ cities have been selected (Rennes, Nantes, Bordeaux and Paris Ile de France). The interviews have been carried out in hyper and super markets (66%); 18% in fishmongers and 16% on markets (key distribution of consumer fresh seafood products behaviour). Three parts will be developed in this article. The first part will expose the buying criteria of fresh seafood products (context, intrinsic and extrinsic attributes). The second part will show the consonance and dissonance results linked to intrinsic and extrinsic criteria (initial and final buying intention). A discussion concerning our global results will be presented. We will do the link with the other results issued from the others methods of our Cogépêche programme.