Abstract: When the regular diagram multiplication method is applied to compute the displacements of beam structures with variable cross-sections, many difficulties will be encountered, such as too much area blocks, excessive numbers of diagram multiplications, great amount of computation, and low computational efficiency. So a new stiffness-distribution diagram multiplication is proposed to solve these difficulties based on the structural stiffness. Basic formulas are derived with operation principles for their applications. The concept of the new method is very clear and can be understood easily, with the advantages of the diagram multiplication method taken fully. The application and the comparison of a numerical case show that the operation of the stiffness-distribution diagram multiplication method is very simple and reasonable. With the new method, small amount of computation is taken with high efficiency. So it is worth being recommended.