Abstract: Numerical simulations and analyses were presented on mixing performance for three different structural micromixers which include ones with circular sub-channel,fan-shaped sub-channel and dislocation sub-channel,respectively.For different Re,the mixing intensity and pressure loss of micromixer were influenced by the geometric structure parameters of the channels.The results show that when Re is more than 10,the mixing intensity of three different micromixers increases as Re increases.In addition,for different Re,the micromixer with dislocation sub-channel acquires the optimal mixing performance,but the pressure loss increases relatively.