For the phenomenon of poor consistency of complex forging blank, there are two kinds of blank processing technology: traditional manual marking with common equipment processing and 3d scanning with 5-axis CNC equipment processing. However, the former has large error and low efficiency and the latter needs large investment and is suitable for a series of prominent problems such as milling. An adaptive clamping technology for complex forging blank based on manipulator was proposed. The manipulator was used to grasp the blank. Through the methods like scanning and taking pictures, the outline of the blank could be perceived. Then the actual model of the blank could be generated. Through the match of the actual model and the theoretical model, the required adjustment of the blank along the workpiece coordinate system was obtained, which was used for adaptive positioning of the blank. The blank was translated into the casting container along the adjusted attitude with the manipulator. Adaptive clamping was achieved by injecting liquid low melting point alloy into the container until it cooled and solidified. Verified by application, the adaptive clamping technology of complex forging blank can be used in turning and milling. The technology with the advantage of stable and reliable quality could meet the actual production demand and has strong engineering application value.