Aiming　at　developing　a　bifunctional　selective　hydrodesulfurization　(HDS)　-　olefin　skeletal　isomerization　catalyst　for　fluid　catalytic　cracking　(FCC)　naphtha　hydro-upgrading,　in　this　article　we　present　an　acid-assisted　dealumination　method,　the　acid-modified　kaolin　(AMK-850-27)　with　tailored　porosity　and　acidity　and　CoMoS　bi-functional　catalysts　CoMo/AMK-850-27　was　obtained.　The　catalytic　performance　was　assessed　with　model　FCC　naphtha　that　is　composed　of　thiophene　(300　mg/kg)　and　1-hexene　(20%)　in　heptane.　Compared　with　two　catalysts　used　γ-Al2O3　and　HZSM-5　as　supports,　CoMoS　catalyst　prepared　with　AMK-850-27　displayed　compromise　catalytic　performance:　balanced　HDS　activity　and　selectivity,　high　skeletal　isomerization　activity　and　low　cracking　activity,　and　excellent　octane　number　preservation　performance.　This　can　be　attributed　to　the　following　reasons:　(i)　AMK-850-27　possesses　micro-meso-macro　porosities　and　appropriate　Brönsted　acidity　that　can　benefit　skeletal　isomerization　activity　but　depress　cracking　activity;　and　(ii)　The　olefin　isomers　are　more　difficult　to　be　hydrogenated　than　the　corresponding　linear　terminal　ones　due　to　the　steric　effect　of　the　branched　olefins.　This　investigation　provides　a　novel　route　to　achieving　deep　desulfurization,　appropriate　olefin　reduction　and　octane　number　preservation　for　FCC　naphtha　upgrading,　acidic　support　with　meso-macro-porosity　can　benefit　olefin　skeletal　isomerization　and　the　HDS　selectivity　but　lower　hydrocarbon　cracking　activity.　©　2022