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In the exterior frame of a super high-rise building, an inclined column and a side column, both being concrete-filled steel tubular columns, intersect with a small angle of 12° to form a huge joint with a height over six stories, and the joint is also connected with six floor beams. Unbalanced axial force exists in the side column over the joint, resulting in unfavorable shear load along the crossover joint. The inclined column is subjected to extremely large axial force. In order to validate its load transfer mechanism, a large-scale test on the joint was conducted in four stages considering the most unfavorable load combination of 1.2 times gravity load and 1.3 times design earthquake action. The test result shows that; in the first stage with design load, the specimen remains in elastic state; secondly, a large increase of unbalanced axial force in the side column has some influence on in-plane lateral displacement and little effect on out-of-plane lateral displacement; thirdly, the specimen remains safe during transition from compression-shear load to tension-shear load through unloading the axial load on the inclined column; lastly the specimen reaches its load carrying capacity which is over twice the design load, and the failure mode exhibits local bulge at both ends of the inclined column due to buckling under compression. There is no obvious deformation within the joint region up to failure, indicating that the design of the crossover joint satisfies the 'strong-joint-weak-member' requirement of Chinese design code. Interior vertical stiffeners and interior steel rings make the steel tubes and concrete work together, preventing obvious shear failure in the joint in the whole process. A 3-D nonlinear finite element model was developed to simulate the mechanical behavior of the crossover joint. The load-deformation curves and failure mode predicted by finite element analyses show good agreement with those of the experiment. [ABSTRACT FROM AUTHOR]