NOVELTY - The hydrocracking reactor comprises a gas-liquid mixture inlet, a reactor tube, a thermometer port, a cold hydrogen feeding port, a gas-liquid mixture outlet and a catalyst discharging port. The reactor tube is placed on a top part of the gas-liquid mixture inlet through a branch tube. The gas-liquid mixture inlet is connected with a spiral type nozzle. The reactor tube is provided with at least two or more catalyst bed layers. An upper part of the catalyst bed layer is provided with a combined type liquid collector distributor by a baffle plate, an air tube and a liquid tube.    USE - The hydrocracking reactor is useful for preparing biological aviation kerosene (claimed).    ADVANTAGE - The reactor has increased hydrocracking efficiency thus increasing the yield of biological aviation kerosene.    DETAILED DESCRIPTION - The hydrocracking reactor comprises a gas-liquid mixture inlet, a reactor tube, a thermometer port, a cold hydrogen feeding port, a gas-liquid mixture outlet and a catalyst discharging port. The reactor tube is placed on a top part of gas-liquid mixture inlet through a branch tube. The gas-liquid mixture inlet is connected with a spiral type nozzle. The reactor tube is provided with at least two or more catalyst bed layers. An upper part of the catalyst bed layer is provided with a combined type liquid collector distributor by a baffle plate, an air tube and a liquid tube. A lower part of the catalyst bed layer is provided with a hump-type mesh plate. The cold hydrogen feeding port is placed on the adjacent catalyst bed layer. A side wall of the catalyst bed layer is placed in a low temperature test hole. The catalyst discharging port is connected with the hump-type mesh plate. The adjacent catalyst bed layer is connected with the gas-liquid mixture outlet through a tube flange. The gas-liquid mixture outlet is placed on the reactor tube. The upper part of the catalyst bed layer is provided with a combined type liquid collector distributor. The liquid tube is located in center of the baffle plate. A lower part of the baffle plate is connected with a discharging tube. The number of catalyst bed layer is 2-5. The hump-type mesh plate has opening rate of more than 70%. The cold hydrogen feeding port is connected with a mosquito-repellent incense having an uniform vent hole in its inner side.