A composition comprising a copolyamide and a crosslinked polyolefin. The present invention relates to a composition comprising at least one semi-aromatic polyamide and at least one crosslinked polyolefin, wherein the crosslinked polyolefin is obtained from at least one product (A) comprising an unsaturated epoxide and from at least one product (B) comprising an unsaturated carboxylic acid anhydride. According to the invention, the weight contents of (A) and (B), denoted respectively [A] and [B], are such that the [B]/[A] ratio is between 3 and 14.