A method for reloading workpieces includes providing a manipulator having a connecting base and a plurality of grasping assemblies arranged on the connecting base, providing a plurality of original workpieces and a plurality of machined workpieces positioned in a plurality of machining positions, grasping the original workpieces by at least one grasping assembly, with at least one grasping assembly vacant, grasping one machined workpiece by one vacant grasping assembly, rotating the connecting base, so that one original workpiece is placed in one machining position by one grasping assembly, further rotating the connecting base until another vacant grasping assembly is opposite to another machining position, and repeating grasping the machined workpieces from the machining positions and placing the original workpieces on the machining positions until a last original workpiece is placed on one machining position. The manipulator used in the present method for reloading workpieces is also provided.