Biopsy rotary cutting device

The present invention provides a biopsy rotary cutting device, which comprises a dynamic sealing structure(4) arranged outside an inner cutting cannula(3); the dynamic sealing structure(4) forms a cavity outside the inner cutting cannula(3); the inner cutting cannula(3) comprises a first tube section(31) and a second tube section(32) that are arranged in sequence along the axial direction of the inner cutting cannula(3); the outer diameter of the second tube section(32) is smaller than that of the first tube section(31); a sealing ring(43) is arranged inside the dynamic sealing structure(4); the cavity comprises a first cavity(41) and a second cavity(42); when the inner cutting cannula(3) moves to a first position along its axial direction, the sealing ring(43) is located at the outer side of the second tube section(32); and there is an inter-cavity gap(46) between the sealing ring(43) and the second tube section(32) to realize communication between the first cavity(41) and the second cavity(42). The present invention can introduce the atmosphere to form a circulating air flow with better suction strength, and the circulating air flow can more efficiently send a rotary-cut tissue at a corresponding position to a sample collector at the back end, thereby effectively improving the sample discharge rate.