The invention relates to the technical field of bio-medical engineering, and particularly relates to a nerve stimulator. The nerve stimulator comprises a substrate provided with a plurality of through holes, a plurality of microelectrodes arranged on the substrate through being filled in the through holes, a stimulus chip and a shell. One side of each microelectrode, leaks out of the substrate, serves as the stimulus part of the microelectrode, while the other side of the microelectrode serves as the connection part of the microelectrode. The connection parts of the microelectrodes are directly inverted and welded onto the stimulus chip. The shell is hermetically connected with the substrate. The manufacturing method of the nerve stimulator is composed of the laser drilling step, the through hole plating step and other machining steps, and the packaging manner thereof is realized through the laser welding step. According to the technical scheme of the invention, the microelectrodes are connected with the stimulus chip through the flip-chip bonding process, so that the tissue damage caused during the implantation process of the nerve stimulator can be greatly reduced. The manufacturing method is simple in process, and short in period. Based on the method, a high-density and orderly-arranged three-dimensional microelectrode array can be implemented. Meanwhile, the high-density selective stimulating and recording function can be realized. Therefore, the nerve stimulator and the manufacturing method thereof have a good application prospect.