A running controller and an electric running control system for an electric vehicle, in which when a tire slip occurs during running of the vehicle, such as under driving, braking and turning, a motor output is controlled to always maximize the coefficient μ of road friction, thereby obtaining a maximum tire driving force and a maximum tire braking force. In the electric vehicle, wheels are driven and braked through control of electric driving apparatuss each including a motor. When slipping of any of the wheels is detected, ESC-CU executes powering and regenerative control of the motor to change, depending on road conditions, a target value to which a slip rate is to be converged. The ESC-CU calculates the coefficient μ of road friction based on a motor current and executes the powering and regenerative control of the motor such that the calculated coefficient μ of road friction is maintained in the vicinity of a maximum value thereof.