Engine exhaust gas purification apparatus and method

In an engine performing a post-injection of fuel for regeneration of a DPF 13 after a main-injection of fuel for securing engine output power, while the post-injection immediately terminates when stoppage of the engine 1 or fuel cut therefor is requested during the regeneration of the DPF, the main-injection does not immediately terminate, but terminates after the execution thereof is continued for a short time. The continued execution of the main-injection for a short time causes post-injection fuel remaining in an exhaust passage 11 to be combusted, thereby preventing the post-injection fuel from being deposited in the DPF 13 .