A wireless input system includes a first computer, a second computer, a first-mode wireless connection device, a first input device and a second input device. When the first-mode wireless connection between the first input device and the first-mode wireless connection device is established and the first-mode wireless connection between the second input device and the first-mode wireless connection device is established, the first input device and the second input device can be operated to control the first computer. When the second-mode wireless connection between the first input device and the second computer is established, the second input device can follow the first input device to perform a connection switching operation. Consequently, the second-mode wireless connection between the second input device and the second computer is established.