A method, device and program for checking and killing a backdoor file and a readable medium, wherein the method comprises: acquiring a historical deletion proportion of a target backdoor file, wherein the historical deletion proportion of the target backdoor file is a ratio of the number of deleting the target backdoor file to the number of symbolizing the target backdoor file as a suspect backdoor file in a preset time period; determining a checking and killing policy corresponding to the historical deletion proportion of the target backdoor file according to a predefined rule; and checking and killing the target backdoor file according to the checking and killing policy. Thus, more processing opinions are provided to the user for reference, so as to facilitate the user in rapidly and efficiently performing accurate processing of the file.