NOVELTY - Separation and purification of carbon dioxide, methane, carbon monoxide and hydrogen from hydrogen production exhaust gas includes adding hydrogen production exhaust gas into first-stage adsorption tower, adsorbing carbon dioxide component, outflowing non-adsorbed intermediate mixed gas into top section of tower, stopping adsorption process, transferring into regeneration process, desorbing adsorbed carbon dioxide component, and discharging carbon dioxide gas; and feeding non-adsorbed intermediate mixed gas into second-stage adsorption tower, adsorbing carbon dioxide.    USE - Method for separation and purification of carbon dioxide, methane, carbon monoxide and hydrogen from hydrogen production exhaust gas (claimed).    ADVANTAGE - The method fully utilizes hydrogen production exhaust gas, and it has reduced pollution on environment.    DETAILED DESCRIPTION - Separation and purification of carbon dioxide, methane, carbon monoxide and hydrogen from hydrogen production exhaust gas comprises:    (A) providing five-stages pressure swing adsorption gas separation unit, adding hydrogen production exhaust gas into first-stage adsorption tower, adsorbing carbon dioxide component, outflowing non-adsorbed intermediate mixed gas into top section of tower, stopping adsorption process, transferring into regeneration process, desorbing adsorbed carbon dioxide component, and discharging carbon dioxide gas into bottom section of tower;    (B) feeding non-adsorbed intermediate mixed gas into second-stage adsorption tower, adsorbing carbon dioxide, outflowing non-adsorbed intermediate mixed gas into top section of tower, stopping adsorption process, transferring into regeneration process, desorbing adsorbed carbon dioxide, and feeding into first-stage adsorption tower gas separation device to carry out boosting;    (C) feeding non-adsorbed intermediate mixed gas into third-stage adsorption tower, adsorbing methane, outflowing non-adsorbed intermediate mixed gas into top section of tower, stopping adsorption process, transferring into regeneration process, desorbing adsorbed methane, and discharging methane gas into bottom section of tower;    (D) feeding non-adsorbed intermediate mixed gas into fourth-stage adsorption tower, adsorbing carbon monoxide, outflowing non-adsorbed intermediate mixed gas into top section of tower, stopping adsorption process, transferring into regeneration process, desorbing adsorbed carbon monoxide, and discharging carbon monoxide gas into bottom section of tower; and    (E) feeding non-adsorbed intermediate mixed gas into fifth-stage adsorption tower, adsorbing carbon monoxide, carbon dioxide, methane and nitrogen, outflowing non-adsorbed hydrogen gas into top section of tower, stopping adsorption process, transferring into regeneration process to obtain carbon monoxide, carbon dioxide, methane and nitrogen as analytical gas, feeding into second-stage pressure swing adsorption gas separation device, purging, and returning back into fifth-stage boosting device to carry out boosting.