Safe remaining needle

The utility model relates to the technical field of medical infusion equipment, in particular to a safety remaining needle which comprises a needle head assembly, an infusion connecting assembly, a communicating pipe and a clamp, the needle head assembly comprises a sleeve seat, a sealing plug and a puncture assembly, the sealing plug and the puncture assembly are arranged in the sleeve seat, and an elastic piece is arranged between the puncture assembly and the sealing plug. The problems that in the assembling process of a traditional remaining needle, due to the fact that a steel needle is too long and is prone to bending in the needle threading process, the quality of finished products is affected, the phenomenon that blood return cannot be observed frequently in the needle inserting process is caused, and the working efficiency of the remaining needle is affected are solved. Meanwhile, in the puncture process, the cannula seat moves towards the retreating position due to the counter-acting force borne by