Abstract: A parallel multilevel fast multipole algorithm (MLFMA) based on OpenMP is proposed and implemented for shared memory parallel platform. According to requirements of efficient OpenMP parallelization and different numerical characteristics of different parts in MLFMA, the parallelization scheme is carefully designed for the establishment of near-field interaction matrix as well as the far-field interaction in matrix vector multiplication in MLFMA. Numerical experiments show that the parallel MLFMA is efficient and has a consistent accuracy with the sequential MLFMA.