The local and total dispersive mixing performance of large type impellers, a standard type of MAXBLEND and double helical ribbons impellers, were numerically analyzed using two indices, local dispersive mixing efficiency and NPD function. The results indicated that a standard type of MAXBLEND has a satisfactory local dispersive mixing performance, especially in the and region where the local dispersive mixing efficiency is high to near 1. However, when the Re is somewhat low, the total dispersive mixing performance is not as satisfactory as that operated under a moderate Re number. The double helical ribbon impeller can not provide a promising local mixing performance, although it can induce a good total circulation throughout the stirring tank.