Self-reconfigurable robots have the ability to change the shape of multiple cooperative modules in the different working environment. One of the main difficulties in building the self-reconfigurable robots is the mechanical complexity and necessary number for achieving certain mechanisms. In this paper, a novel design of a self-reconfigurable robot, called "Octabot", is described. The Octabot robot is a two-dimensional self-reconfigurable robot with modules composed of eight e-type electromagnet actuators. The magnetic force characteristics based on FEM are first analyzed, and mechanical design and system properties are described in detail. A group of Octabots can be easily expanded to a large scale if needed in any case. Via examining the basic mechanical functionalities, the Octabot in self-reconfiguration shows its satisfactory performance.