To evaluation properly the economical benefit from the application of achievements to scientifit and technical difficulty overcoming is important for the application of science and technology in economy. This paper analyses the way of the generation of the economical benefit from the application of achievements in scicntific and technical difficulty overcoming and presents a model for evaluating the bencfit-cost ratio of the economic benefit from the application of achievements in scientific and technical difficulty overcoming, baaed on the analysis of both manufactuning processes and scientific and technical difficuty overcoming.