The use of concrete-filled steel tubes in different areas of construction is becoming an attractive solution because of its remarkable performance. It provides not only an increase in the load carrying capacity but also good seismic behaviour. It is often adopted as compression member especially for structure under large axial pressure. Concrete-filled steel tubular composite truss can be used as main load-bearing structure of long-span and mega structure. But the composite trusses were connected by mutually intersecting joints which the welding construction process is complicated and the quality is unstable. Therefore, gusset plate joints are more suitable. So experimental study and finite element analysis are carried out in 12 specimens. Test results indicate that bearing capacity of hollow circular steel tube joints filled with concrete is provided obviously, and local buckling performance of steel tube under gusset plate is also improved. In order to study the mechanical performance and interaction of steel tube and core concrete, the ANSYS program is adopted in finite element analysis. And the analysis results is agreed well with the test. Regression analysis is carried out at the same time, thus simplified calculated formula of this type joints is concluded which can give reference for the designers.