To investigate the mechanical properties of steel bamboo I section composite column under long term loading, 18 specimens were designed and manufactured. Static loading test, long term loading test and secondary static loading test were carried out successively, in which the creep process were measured and analyzed, influencing factors of bearing capacity and deformation and their variation rule were studied. Results show that the steel bamboo I section composite column has high integrity and bearing capacity, the creep deformation reached 90% of the total creep when loaded for 60days, the Burger model can accurately describe the creep process of the composite column. The ductility and ultimate strain are significantly increased after long term loading, while the ultimate bearing capacity is not greatly affected,the bearing capacity and ductility are improved with the increasement of steel ratio.