Medical needle tensioner

The invention discloses a medical needle tensioner. A fixed seat is internally provided with a first threaded hole and a first inner cavity which are communicated from front to back in sequence, a guide needle mouth provided with a guide needle hole is arranged in the first threaded hole, and a sliding seat is arranged in the first inner cavity and can move front and back in the first inner cavity under driving of a driving mechanism; the sliding seat is internally provided with a cone-shaped through hole, a second inner cavity and a second threaded hole which are communicated from front to back in sequence, a spring pressing screw is arranged in the second threaded hole, a claw jacking rod is arranged in the second inner cavity, a compressed spring is arranged between the claw jacking rod and the spring pressing screw, multiple clamping claws are arranged in the cone-shaped through hole, the clamping claws jointly form a needle clamping gap which allows a medical needle to pass through and is communicated wi