Jigger is the main equipment in coal processing industry in China, which is developed towards large-scaledevice. By using the homemade device LTX-35 jigger as a model employing mesh division with non-orthogonalmesh for different kinds of through-flow passage, and completing the numerical simulation with the computationalfluid dynamics (CDF) software-PHOENICS, the velocity distribution in different flow fields resulting from guideplates of varied structures are obtained. The results from the simulation show that 1) the degree of velocityuniformity of the flow field can be improved if a flat guide plate is replaced by a curved one in the jigger;2) the bestresult can be achieved by using a semicircular guide plate.