In a method for aligning a part of a product (moving object) with a reference object, triangle data of the moving object is acquired, and feature elements of the moving object is fitted according to the triangle data. Feature elements of the reference object which match the feature elements of the moving object are determined, and the moving object is moved from a position of a center point of the feature elements of the moving object to a position of a center point of the matched feature elements of the reference object. A moving-and-rotating matrix of the moving object is obtained according to Quasi-Newton methods, and the moving object and the reference object are aligned by moving and rotating the moving object according to the moving-and-rotating matrix.