Disclosed are a power saving method for a terminal device and the terminal device thereof, wherein the method includes: a terminal device enabling a power saving mode and obtaining an adjusted central processing unit (CPU) clock speed set by a user and an adjusted screen resolution set by the user; if the terminal device obtains the adjusted CPU clock speed set by the user, the terminal device adjusting the CPU to operate according to the adjusted CPU clock speed set by the user; if the terminal device obtains the adjusted screen resolution set by the user, the terminal device adjusting a screen display according to the adjusted screen resolution set by the user. The embodiment of the present document saves the power consumption of a terminal device by downsizing the screen display and/or reducing the CPU clock speed, thereby effectively reducing power consumption of the terminal device.