The aquaculture sector is the world’s most important fish food provider for human consumption. Fishmeal, the most expensive protein source in aquafeed which leads low income and environment pollution. Therefore aquaculture is looking for alternative suitable protein sources, which could replace this limited resource. A useful protein source from the by-products of rapeseed oil production, cake or meal, has been suggested as an alternative to fishmeal for aquafeed. Unfortunately the rapeseed meal contains some antinutritional factors (ANFs) such as glucosinolates, phenolic compounds (tannins and phenolic acid), phytic acid and indigestible carbohydrates. These antinutritional substances can affect negatively on the fish growth performance and health status, but the level of ANFs are reduced by heat treatment. Due to wide availability, high protein content and a desirable amino acid profile have caused an interest in rapeseed products as fish meal alternative in aquafeeds.