Abstract: An omnidirectional mobile microrobot with a size of 9 mm×8 mm×8 mm is introduced.Pure rolling movement between the wheels and the ground are achieved with a novel dual-wheel structure.The microrobot is driven by three electromagnetic micromotors with 2 mm diameter.Two of the micromotors are for translation and the other one is for steering.Dynamics is analyzed to unveil the relation between the micromotor torque and the dual-wheel structure size as well as various frictions.Simulation and experiment results demonstrate that the microrobot has good load-carrying ability and satisfies the requirements of handling task in a microfactory.