This　paper　presents　a　numerical　study　on　the　dynamic　characteristics　of　gas　foil　thrust　bearings　for　supercritical　carbon　dioxide(S-CO2)cycles.　Based　on　the　finite　element　analysis　software　ANSYS　and　the　computational　fluid　dynamics　software　CFX,　a　full　three-dimensional　(3D)　unsteady　fluid-structure　coupled　numerical　method　was　proposed　and　validated　for　predictions　of　the　dynamic　characteristics　of　gas　foil　thrust　bearings.　The　dynamic　stiffness　and　damping　coefficients　were　calculated　and　analyzed　for　a　gas　foil　thrust　bearing　at　6　working　medium　temperatures,　5　working　medium　pressures,　7　gas　film　thicknesses　and　6　disturbance　frequencies,　by　adding　axial　periodic　excitations　on　the　bearing.　The　influences　of　operating　parameters　on　the　dynamic　performance　of　S-CO2　gas　foil　thrust　bearing　were　presented.　©　2020,　Science　Press.　All　right　reserved.