Bidirectional filter syringe needle

The invention provides a bidirectional filter syringe needle which comprises a steel needle, an upper needle base, a lower needle base, a check valve, a sealing gasket and filter membranes, wherein a lower needle base cavity and a check valve cavity are arranged at the rear end of the upper needle base, the check valve cavity comprises a circular truncated cone inner side wall and a cylindrical inner side wall, an annular groove is formed in the end face of a small end of the circular truncated cone inner side wall, the center of the annular groove is communicated with a steel needle installation hole, a large end of the circular truncated cone inner side wall is connected with the cylindrical inner side wall, a groove connected with the annular groove is formed in the circular truncated cone inner side wall, a triangular plate is perpendicularly arranged at the bottom of the annular groove, a connecting part is arranged at the front end of the lower needle base, a valve element is arranged in the center of the connecting part, the annular filter membrane sleeves the rear end of the valve element, the round filter membrane is arranged at the end part of the rear end of the valve element, a check valve cylinder sleeves the valve element, the sealing gasket is arranged at the front end of the check valve cylinder at the end part of the valve element, and the connecting part is inserted into the lower needle base cavity. The filtering and injecting processes of the bidirectional filter syringe needle are carried out automatically, so that the bacterial and viral pollution is avoided.