The invention relates to a curved pipe shape detection system and a detection method. The curved vascular detection system comprises a numerical control pipe-bending machine, a pipe shape detection apparatus and a control system used for processing the detection information, the pipe shape detection apparatus used for measuring the rebound distance of the pipe is arranged on the numerical control pipe-bending machine, and is positioned at same plane with a processing pipe fitting of the numerical control pipe-bending machine; the pipe shape detection apparatus is connected to the control system, and a rebound angle of the pipe fitting can be calculated by using a geometry principle. According to the invention, the rebound distance of the pipe fitting can be measured according to the distance change between the pipe shape detection apparatus and the pipe fitting before and after rebound, so that a rebound value of the pipe fitting can be rapidly calculated. In the invention, the curved pipe shape detection system enables on-line direct detection on the numerical control pipe-bending machine, secondary error due to multitime clamping can be avoided, the detection system and detection method are convenient and fast, and the detection system is suitable for batch detection, error overlaying between multiple bends of the pipe fittings can be avoided, and detection precision can be enhanced.