Lonchodryinus groehni sp. nov. (Hymenoptera: Chrysidoidea: Dryinidae) is described from Baltic amber. The new species is close to L. balticus Olmi Guglielmino, 2012, but it can be distinguished for the different OPL/POL ratio and 2r-rsRs vein of the fore wing. A key to the fossil species of Lonchodryinus and a comparison with the extant species L. ruficornis (Dalman, 1818) are presented.