The　impurity　metal　of　Al　in　spent　hydroprocessing　catalyst　(Mo-Ni/Al2O3)　was　removed　by　HCl,　and　the　metals　of　Mo　and　Ni　were　preliminarily　enriched.　The　results　show　that　the　leaching　efficiency　of　Al　was　88.62%,　and　the　leaching　efficiency　of　Mo　and　Ni　were　16.32%　and　28.74%,　respectively.　The　results　were　achieved　under　optimal　leaching　conditions:　the　particle　size　was　150　μm,　the　concentration　of　HCl　was　4　mol/L,　the　leaching　temperature　was　90　°C,　and　the　leaching　time　was　120　min.　The　kinetics　of　the　leaching　behavior　of　Al　showed　that　the　acid　leaching　reaction　of　Al　was　in　accorded　with　the　equation　1-2/3X-(1-X)2/3=K2t,　R2=0.97734,　which　was　controlled　by　internal　diffusion.　X-ray　diffraction　analysis　of　the　leaching　residue　revealed　the　existence　of　residual　metals　Mo(MoO3,　MoO2(ClO4)2)and　Ni(NiS).　The　separation　of　Al　from　Mo　and　Ni　has　been　preliminarily　realized,　which　is　conducive　to　further　efficient　recovery　of　Mo　and　Ni.　©　2020　Trans　Tech　Publications　Ltd,　Switzerland.