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A beam-column fiber element for the large displacement, nonlinear inelastic analysis ofConcrete-Filled Steel Tubes (CFT) is implemented. The method of description is Total Lagrangianformulation. An 8 degree of fredom (DOF) element with three nodes, which has 3 DOF per end nodeand 2 DOF on the middle node, has been chosen. The quadratic Lagrangian shape functions for axialdeformation and the quartic Hermitian shape function for the transverse deformation are used. It isassumed that the perfect bond is maintained between steel shell and concrete core. The constitutivemodels employed for concrete and steel are based on the results of a recent study and include theconfinement and biaxial effects. The model is implemented to analyze several CFT columns underconstant and non-proportional fluctuating concentric axial load and cyclic lateral load. God agreementhas been found between experimental results and theoretical analysis.