An electronic system and a control method thereof are provided. The electronic system includes a first device, a second device and a control device. The first device includes a first processor and a first control module, and the first control module is electrically connected to the first processor. The second device is detachably disposed on the first device. The second device includes a second processor and a second control module, and the second control module is electrically connected to the second processor. The control device is detachably connected to the second device, and the first device, the second device and the control device are coupled to each other.