Abstract: In order to improve the drilling efficiency of diamond drill bits, the bit structure is reasonably designed to ensure that the bit has a good cooling and chip removal ability during the drilling process, so as to avoid abnormal wear caused by excessive rise of the temperature at the bottom lip of the bit. Numerical simulation and experimental research are used to study the distribution of flow field and temperature field at the bottom of the impregnated diamond drill bit. The results show that the lateral pressure generated by the flow field has a great effect on the pressure destruction of the nozzle wall. According to numerical simulation and drilling tests, the temperature of the contact surface between the drill and the rock is related to the number of nozzles but excessive nozzles will decrease the flow rate of drilling fluid in a single nozzle and thus decrease the heat transfer efficiency at the nozzle. Therefore, the cooling effect is reduced and the drill bit wears fast.