The invention concerns an opening aid (1) for an energy guide chain (E) with chain links (K). At least some of the chain links (K) at their top side have a respective transverse leg (Q) which is arranged pivotably on a side plate (L) and which can be fixed to the other side plate (L). The opening aid (1) for guidance of the transverse legs (Q) upon opening thereof has a body (2) extending in a working direction (a) and a lateral extension (4) having an inclined sliding deflection surface (3) for the transverse legs (Q). To simplify handling and structure of the opening aid (1) it is proposed that the extension (4) is mounted to the body (2) movably relative thereto and is reciprocatingly movable between a working position in which the extension (4) is arranged extending laterally from the body (2) in operative guiding relationship for the transverse legs (Q) and a rest position in which the extension (4) is arranged in inoperative guiding relationship of being moved away from the working position.
