Method, system and device for downloading file

The invention discloses a method, a system and a device for downloading a file. The downloading method comprises the following steps of: acquiring useless data in the file to be downloaded; removing the useless data in the file to be downloaded, and compressing the file to be downloaded; and downloading the compressed file to be downloaded to a memory of terminal equipment. Thus, according to the invention, it is possible to improve the efficiency of file transmission, save costs of production and after-sale service, and prolong the service life of the memory of the terminal equipment.