A tissue closure device comprising: a first clamping base and a second clamping base configured to be opened/closed relatively and form an accommodation cavity after being closed, wherein: each of the first clamping base and the second clamping base comprises a clamping housing, a clamping plate fixed in the clamping housing, and a channel which is located between the clamping housing and the clamping plate and extends from a proximal end to a distal end; each of the clamping plates on the first and second clamping base (11, 12) is provided with convex blocks; a needle groove which penetrates through the convex block from the proximal end to the distal end and is communicated with the accommodation cavity is arranged on each of the convex blocks; and the convex blocks on the clamping plates of the first clamping base and the second clamping base are staggered from the proximal end to the distal end; a pouch assembly configured to be driven to move from the proximal end to the distal end comprises a staple pusher, a pair of needle heads (2411, 2412) movably connected to the staple pusher, and a connection portion connected to the proximal ends of the pair of needle heads (2411, 2412), wherein when the staple pusher moves from the proximal end to the distal end, the pair of needle heads (2411, 2412) respectively is configured to move in the needle grooves of the convex blocks on the clamping plates of the first clamping base and the second clamping base, is configured to pierce into a tubular tissue; characterized in that each of the clamping plates on the first and second clamping base (11, 12) is provided with a plurality of openings which is arranged at intervals from the proximal end to the distal end and communicated with the channel and the accommodation cavity, the convex blocks are located in the openings respectively and configured to get close to or apart from the clamping housing in the openings in the direction perpendicular to the clamping plate; the tissue closure device further comprises a pushing block configured to be driven to move from the proximal end to the distal end in each of the channels to successively drive the convex blocks on the clamping plate to move in the direction away from the clamping housing, wherein after the pushing block moves towards the distal end, the convex block located at the proximal end of the pushing block is configured to disengage from the pushing block; wherein the pair of needle heads (2411, 2412) is configured to gradually push the tubular tissue to the distal end and gather the tubular tissue until the distal ends of the pair of the needle heads (2411, 2412) are closed to close the tubular tissue into a purse string. each of the first clamping base and the second clamping base comprises a clamping housing, a clamping plate fixed in the clamping housing, and a channel which is located between the clamping housing and the clamping plate and extends from a proximal end to a distal end; each of the clamping plates on the first and second clamping base (11, 12) is provided with convex blocks; a needle groove which penetrates through the convex block from the proximal end to the distal end and is communicated with the accommodation cavity is arranged on each of the convex blocks; and the convex blocks on the clamping plates of the first clamping base and the second clamping base are staggered from the proximal end to the distal end; a pouch assembly configured to be driven to move from the proximal end to the distal end comprises a staple pusher, a pair of needle heads (2411, 2412) movably connected to the staple pusher, and a connection portion connected to the proximal ends of the pair of needle heads (2411, 2412), wherein when the staple pusher moves from the proximal end to the distal end, the pair of needle heads (2411, 2412) respectively is configured to move in the needle grooves of the convex blocks on the clamping plates of the first clamping base and the second clamping base, is configured to pierce into a tubular tissue; characterized in that each of the clamping plates on the first and second clamping base (11, 12) is provided with a plurality of openings which is arranged at intervals from the proximal end to the distal end and communicated with the channel and the accommodation cavity, the convex blocks are located in the openings respectively and configured to get close to or apart from the clamping housing in the openings in the direction perpendicular to the clamping plate; the tissue closure device further comprises a pushing block configured to be driven to move from the proximal end to the distal end in each of the channels to successively drive the convex blocks on the clamping plate to move in the direction away from the clamping housing, wherein after the pushing block moves towards the distal end, the convex block located at the proximal end of the pushing block is configured to disengage from the pushing block; wherein the pair of needle heads (2411, 2412) is configured to gradually push the tubular tissue to the distal end and gather the tubular tissue until the distal ends of the pair of the needle heads (2411, 2412) are closed to close the tubular tissue into a purse string.