The method and apparatus support signature-based application management that examines credibility of an application to be installed or executed and controls installation and execution accordingly. The application management method for a user device includes: receiving user input for installing an application; comparing signature information of the application with an authentication list stored in a signature information storage; preventing, when the signature information is present in a blacklist of the authentication list, installation of the application; initiating, when the signature information is present in a whitelist of the authentication list, installation of the application; and selectively performing, when the signature information is not present in either the blacklist or the whitelist, installation of the application according to user consent.