The present study has been performed to develop a PCR technology to identify human immunoglobulin(Ig) allotypes with restriction fragment length polymorphism(RFLP) using a probe. Genomic DNA were ampilified with PCR tecnology using primers from peripheral blood lymphocytes of 10 periodontal patiens, whose Ig allotypes have been pre-determined by serological tecnique using heagglutination technique. The result indicated that the RFLP patterns could successfully differentiate the Ig allotypes, which suggests that this technology can be developed as a tool useful for population genetics studies.