To　study　the　mechanical　behavior　of　recycled　aggregate　concrete　filled　square　steel　tube　long　columns　under　eccentric　compression　loading,　15　specimens　were　designed.　Three　test　parameters　were　considered　in　the　test,　which　were　recycled　coarse　aggregate　replacement　percentage,　slenderness　ratio　and　load　eccentricity　ratio.　From　the　test,　the　failure　patterns,　load-displacement　curves,　load-strain　curves,　cross-section　strain　distribution　and　the　bearing　capacity　were　obtained,　and　the　influences　of　three　parameters　were　analyzed.　The　existing　related　standards　of　China　and　other　countries　were　used　to　calculate　their　bearing　capacity.　The　calculation　results　were　analyzed　and　compared　with　measured　results.　The　results　of　study　show　that　the　bearing　behavior,　failure　modes,　deformation　features　and　section　distribution　of　recycled　aggregate　concrete　filled　square　steel　tube　long　columns　are　similar　to　the　normal　concrete　filled　steel　tubular　columns.　The　recycled　aggregate　concrete　filled　square　steel　tube　long　columns　under　eccentric　compression　loading　has　the　same　bearing　capacity　and　deformation　capacity　as　ordinary　concrete　columns.　The　recycled　coarse　aggregate　replacement　percentage　has　no　influence　on　the　specimens　bearing　capacity,　which　is　in　inverse　proportion　to　the　slenderness　ratio　and　eccentricity.　The　bearing　capacity　of　the　recycled　aggregate　concrete　filled　square　steel　tubular　long　columns　calculated　according　to　the　standard　DBJ　13-51-2003　is　in　good　agreement　with　the　test　results.　The　results　can　provide　reference　and　basic　for　further　research　and　application　of　the　recycled　concrete　filled　square　steel　tubes.