Triangular and circular needles are surgical needles used clinically to suture tissues. Generally speaking, the difference between round needles and triangular needles are mainly the following: First, the difference in appearance, round needles have a more rounded tip, which is less damaging to the tissues, while triangular needles have a triangular tip and a very sharp tip. Triangular needles can also be divided into large triangular needles and small triangular needles. Second, the difference in use, due to the sharp tip of the triangular needle, mainly used for skin and other tough tissues of the interrupted suture and skin reduction suture. Round needle tip is more rounded, for tissue damage is smaller, so the round needle is widely used in the abdominal cavity intestinal anastomosis, gastrointestinal perforation repair, peritoneal closure, vascular suture, and so on.