In  ord er to a chieve t he goal  of re duci ng car bon and saving e nergy by u sing alcoho l blende d fuel on s park ignition engine, bas ed o n LJ4 K1 8QS eng ine modeling, the alcohol ble nded fuel was us ed to op timiz e the operati ng param eters,  an d the i nfluence of air-fue l rat io and ig nition advance angle on engine power, economy and emission characteristics were reve aled . The re sult s show  that un der loa d chara cteri stics, with the increase of air -fuel rati o, engine torque and NOx emission s increase f irstly and then decrea se, e ngine fuel con- sumpt ion decrea ses and then inc reases, CO emissio ns de- crease gradually and H C emission s in crease graduall y. As the ignitio n ad vanc e angle dec reas es, t he engine tor que incre ases firstly and then de creases , the fuel consumpti on rate and CO emission s decrease firs tly a nd then i ncrease, NOx emissi ons dec rease gradu ally and HC emissio ns in crea se gradu ally. At the s am e ti me, the optimu m air-fue l ratio and ignition a dvance ang le of the en gine under different l oad s are obtain ed, which can provide the theo retical refer ence for subsequent research.