The present invention provides a feed for a farmed fish, which contains an animal raw material, a part or the whole of which has been substituted with a plant raw material, and/or a plant raw material as a protein source, and can prevent a decrease in growth efficiency and feed efficiency for fishes, a method for promoting the growth of a farmed fish using the feed for a farmed fish, and an additive for a feed for preparing the feed for a farmed fish. The present invention relates to a feed for a farmed fish, which contains an animal raw material, a part or the whole of which has been substituted with a plant raw material, and/or a plant raw material as a protein source, and is characterized by containing at least one amino acid selected from the group consisting of alanine, glutamic acid, glutamine, proline, ornithine, citrulline, and arginine.