Ten　high　strength　steel　columns　with　the　same　cross-section　and　length　were　designed　and　divided　into　two　groups　according　to　axial　and　eccentric　compression.　In　each　group　of　five　specimens,　one　column　did　not　go　through　the　heating　and　cooling　cycle　and　was　loaded　until　failure　at　ambient　temperature　to　obtain　its　load　carrying　capacity　without　being　heated.　The　other　four　columns　were　axially　restrained,　heated　to　target　temperatures　and　cooled　down　to　ambient　temperature　in　air　under　sustained　applied　loads,　and　then　load　tested　to　failure　at　ambient　temperature　to　obtain　their　post-fire　load　carrying　capacity　(residual　capacity).　The　behaviors　of　axially　restrained　high　strength　steel　columns　under　fire　and　after　fire　were　obtained,　and　corresponding　numerical　simulations　were　conducted.　It　was　found　that　after　the　axially　restrained　high　strength　steel　columns　underwent　overall　buckling　at　elevated　temperatures,　the　lateral　deflection　developed　rapidly,　and　retained　significant　lateral　deflection　after　fire,　resulting　in　significant　reduction　of　the　post-fire　residual　capacity.　Under　the　same　condition,　the　post-fire　residual　capacity　reduction　degree　of　axially　restrained　high　strength　steel　columns　decreased　with　the　eccentricity.　The　behavior　of　axially　restrained　high　strength　steel　columns　during　the　whole　heating　and　cooling　process　and　after　fire　can　be　simulated　reasonably　well　using　the　numerical　model　proposed　in　this　study.　©　2025　Chinese　Society　of　Civil　Engineering.　All　rights　reserved.