This study was investigated to determine the amino acid content, fractionation and gel electrophoresis pattern of mungbean protein isolates(MPI), which were prepared from defatted mungbean flour(DMBF) of sunhwa-nogdu(SH) and conventional(C) mungbean varieties. MPI have particulary high content of lysine and low sulfur containing amino acids, even though amino acid pattern of mungbean flour and its protein isolate were found to be similar And, there was no significant difference In the amino acid composition between SH and C varieties. Further fractionation of MPI by solubility method and electrophoresis procedure was demonstrated that the fractions, such as albumin, globulin, glutelin and residue from MPI showed $6{sim}10$ bands in SDS/PAGE pattern. And also the most of each protein fractions had lower molecular weight than 68,000 daltons and distributed more in the molecular weight range $43,000{sim}68,000$ daltons.