A new kind of numerical method, Contact Element Method (CEM) with two relative coordinates, has been proposed. There are two main characteristics in this method. First, meshing is based on the contact length between the rolls or between the work roll and the strip; second, two relative coordinates are established for every element depending on the contact objects. A matrix for analyzing the rolling process of a Sendzimir mill has been established as well as a software SM4SM (Setup Models for Sendzimir Mill) by which the strip edge drop during rolling has been studied using the CEM. The calculated results show that the strip edge drop will decrease when increasing the 1st intermediate roll (IMR) taper slope and length, reducing the 1st IMR shifting, increasing the roll J and the work roll crown, or increasing the tension stress; by contraries, the strip edge drop will increase. Meanwhile, three methods (changing the work roll crown, changing the work roll edge rigidity, changing the pressure distribution on the work roll) for controlling the strip edge drop are discussed.