Abstract: Abstracts: Diesel dual-carrier oxidation converters are widely used in diesel engine emission control, but there are problems such as short service life and low efficiency are caused due to excessive pressure loss and uneven flow in the process. In order to address this series of problems, a parametric design and optimization method for the structure of dual-carrier oxidation converter are proposed, which are used to improve the flow characteristics of the oxidation converter, namely the pressure loss and flow uniformity. A three-dimensional flow model of the oxidation reformer was established to analyze the influence of the total length of the carrier, the ratio between the gap of the double carriers and the total length of the carrier, and the ratio of the length of the carrier before and after the double carriers on the flow characteristics of the oxidation reformer. Based on the Box-Behnken experimental design and the response surface method, the flow characteristics of the two-carrier oxidation converter are studied, with the total length of the carrier, the ratio between the gap of the two carriers and the total length of the carrier, and the ratio of the length of the carrier before and after the two carriers as the optimization quantities, and the pressure loss and flow uniformity as the optimization objectives for the response surface analysis, and combined with the NSGA–Ⅱ genetic algorithm for the optimization. The results showed that the pressure loss inside the oxidation reformer was reduced by 15.24% and the flow uniformity was improved by 6.44%. This study provides a reference for the structural design of dual-carrier oxidation reformer.