Proposed are a robot cleaner having an improved wheel structure to escape from being stuck in various travel conditions, and a control method thereof. The robot cleaner may smoothly escape from a door sill or an obstacle to stably travel irrespective of a state of a floor by providing an optimal frictional force of the floor through the control of an electric current of a motor when the robot cleaner escapes from being stuck. Also, the robot cleaner may stably travel without shaking by controlling an electric current flowing through the motor after the robot cleaner escapes from being stuck and before the driving wheel returns to a normal mode. Furthermore, it is possible to prevent a wheel mechanism such as a gear from being damaged by an external shock (e.g., which is caused by a pet or an object drop) or a shock caused by autonomous vibration when the robot cleaner crosses over an obstacle.