Calculating　method　and　construction　details　are　being　critical　issues　for　designing　connections　to　concrete　filled　steel　tubes　(CFST).　This　paper　presents　a　state　of　the　art　review　in　research　on　the　behavior　of　CFST　columns　to　steel　beam　and　reinforced　concrete　beam　connections.　The　connection　types　and　their　characters　are　summarized,　based　on　the　past　researches　and　experiences.　This　paper　identifies　a　number　of　key　issues　for　future　research,　including　mechanics　model,　simplified　design　method,　the　determination　of　bond　strength　between　the　steel　tube　and　the　concrete　core,　the　fire　and　post-fire　performance　of　connections.