The present invention relates to a radioimmunoconjugate that binds human CD37comprising a) an anti-CD37 antibody comprising an immunoglobulin heavy chainand an immunoglobulin light chain, wherein the heavy chain comprises the aminoacid sequence of SEQ ID NO: 2 and the light chain comprises the amino acidsequence of SEQ ID NO: 4; b) a chelating linker; and c) a radionuclideselectedfrom the group consisting of 177Lu, 225Ac, 227Th, 212Pb and 90Y.