Hypera postica is currently the main pest of alfalfa over the world. In Spain, damages are produced during alfalfa first cutting, its control is not resolved and little is known about biological control. Parasitoids of the genus Bathyplectes sp. occurs along the weevil larval development. The rates of parasitism by Bathyplectes anura and Bathyplectes curculionis were recorded during eleven years. They varied between fields and years but B. anura was the prevalent species. Yearly total parasitism rates ranged from 1% to 31%, averaging from 13.8% to 6.2% at the beginning and the end of April, respectively.