A spring needle with an improved structure comprises a needle shaft, a spring and a needle tube. The spring is arranged between the needle tube and the needle shaft; the shaft end surface where the needle shaft and the spring are elastically contacted is an inclined surface; the lower outer circumferential surface of the needle shaft is provided with a protruding part; the protruding part is provided with a plurality of ball grooves; balls are installed inside the ball grooves; the diameter of the ball is larger than the depth of the ball groove; and the balls are dynamically matched with the inner wall surface of the needle tube. The spring needle with an improved structure has the advantages of simple structure, reasonable design, long service life, high use performances and the like.