This　paper　applied　an　optimized　transmitting　boundary　with　multiple　artificial　velocities　(denoted　as　caj-MTF)　that　is　recently　proposed　by　the　authors　to　the　high-accuracy　spectral-element　simulation　of　seismic　wave　propagation,　and　made　a　comparison　study　with　several　other　classical　artificial　(or　absorbing)　boundary　conditions　including　Liao＇s　multi-transmitting　formula　(MTF)　boundary,　perfectly　matched　layer　(PML)　boundary,　viscous-spring　boundary　and　the　first-order　Clayton-Engquist　paraxial-approximation　boundary.　The　results　obtained　from　theoretical　analysis　and　numerical　tests　are　as　follows:　①　The　formulation　of　ca　j-MTF　is　very　similar　to　that　of　MTF,　so　it　has　most　of　the　advantages　of　the　latter,　i.e.,　very　simple　expressions,　easy　to　be　implemented,　adjustable　accuracy,　minimal　computation　cost,　and　general　applicability.　②　Unlike　the　traditional　MTF　boundary　that　has　only　a　single　artificial　wave　velocity　(i.e.,　computational　wave　velocity),　ca　j-MTF　has　multiple　artificial　wave　velocities.　In　the　simulation　of　elastic　waves,　the　computational　wave　velocity　parameters　of　ca　j-MTF　can　be　set　to　be　P-　and　S-wave　velocities,　respectively.　On　this　situation,　the　consistency　between　computational　and　physical　wave　velocities　makes　a　significant　improvement　in　the　boundary　accuracy.　③　ca　j-MTF　boundary　has　an　slightly　lower　accuracy　than　that　of　PML　boundary,　whereas　it　is　significantly　superior　to　MTF,　viscous-spring　boundary　and　the　first-order　paraxial-approximation　boundary.　④　ca　j-MTF　is　superior　to　PML　as　it　has　much　simpler　formulations　and　better　versatility.　This　work　provides　a　convenient　and　high-efficient　artificial　boundary　(or　absorbing　boundary)　for　spectral-element　simulation　of　seismic　wave　propagation.　Copyright　©2022　ACTA　SEISMOLOGICA　SINICA.　All　rights　reserved.