Abstract: During the operation of the FCC gasoline selective hydrogenation unit of a petrochemical company, the Research Octane Number (RON) of the product was low. The cause which led to the low RON of product included: (1) the selectivity of selective hydrogenation catalyst was poor; (2) the carbon six olefins saturated seriously; (3) the isoamylene etherification rate was low. By taking the measures including optimizing the reaction conditions of selective hydrogenation, increasing the light gasoline extraction rate and the etherification reaction temperature, the RON of selective hydrogenation product, gasoline product and etherification gasoline increased 1.5 units, 0.5 units and 0.05 units, respectively.