The invention discloses a method and a system for identifying and positioning targets on the basis of three-dimensional point cloud. The method and the system have the advantages that procedures for identifying and positioning target workpieces during industrial production feeding and discharging are divided into an offline feature extracting module and an online feature matching module, accordingly, the computational complexity in real-time phases can be reduced to a great extent, and the arithmetic speeds can be increased; matching quality estimation is introduced to obtain accurate three-dimensional locations and gestures of the workpieces, and accordingly industrial robots can grab the identified workpieces in corresponding gestures under the control; the method and the system are different from target identifying and positioning algorithms customized and developed for local geometric shape features (such as circles and holes) of existing workpieces, the targets can be universally identified and accurately positioned by the aid of the method and the system, accordingly, algorithms do not need to be redeveloped for the different workpieces, and the development time can be saved; the problem that the existing workpieces are required by the traditional feeding and discharging schemes for robots to be fed into visual fields of existing cameras according to certain gestures can be solved, the method and the system are free of optional requirements on the gestures of the workpieces in visual fields of cameras, and the workpieces can be arranged in a scattered manner or can be stacked on one another or can be shielded by one another.