An adjusting method of a virtual keyboard adapted to a first touch device is disclosed. The first touch device displays a virtual keyboard with several keys. The adjusting method includes the following operations: adjusting a position and a size of the virtual keyboard displayed on the first touch device according to an operating range of a user; collecting several first click points on the virtual keyboard and one of the keys corresponding to the first click points; analyzing several press distributions of the keys according to the first click points; determining one of the keys corresponding to a second click point according to the press distributions and center points of the keys; transmitting the press distributions and the position and the size of the virtual keyboard to a server; and transmitting the press distributions and the position and the size of the virtual keyboard to a second touch device.