The goals of this research are to understand the regeneration characteristics in diesel particulate filter using the HC injection. This research emphasized on the development of Continuously Regenerating DOC/DPF and HC technology which was the best particulate matters removing technology of current existing technology. This experimental study has been conducted with equipped a Continuously Regenerating DOC/DPF and HC injection on displacement 2.0, 3.3 $ell$ diesel engine and compared in terms of particulate material and emission. In this study, we could constructed 3 kinds of database according to quantity of temperature to decide the HC injection quantity and develop DOC/DPF ECU algorithm.