Abstract: To study the shear strength of composite column whose steel tube has large openings and to study the effects of strengthening measures，4 concrete-filled steel tube composite column specimens were tested，in which one specimen had no opening on its steel tube wall and 3 specimens had large openings on their steel tube wall． The test results showed that all the specimens failed in shear; openings on the steel tube wall decreased the shear strength of the specimens． The strengthening measures increased the shear strength of specimens whose steel tube had large openings． The formulas to calculate the shear strength of concrete-filled steel tube composite columns whose steel tube had large openings were proposed，the calculated shear strength of the specimens had good agreement with the test results．