Abstract: As a typical aerospace structure, the axial compression stability of composite grid stiffened cylinder determines the ultimate bearing capacity of the spacecraft structure. The homogenization equivalent method and beam-shell finite element method which have been researched are deficient. The local stress and stability of grids were taken into consideration, the grids were equivalent to shell elements, and the all-shell finite element method was put forward. Depending on the composite grid stiffened cylinder of certain aircraft, the three methods were used to study the axial compression stability respectively. Meanwhile, a full-size axial compression destruction test was also designed. Good agreement was achieved in the comparison between the numerical simulation and test results, which verified the rationality of the aircraft design. The deviation between the homogenization equivalent method, the beam-shell finite element method, the all-shell finite element method and test value are 14.9%, 9.5% and 5.2% respectively. The all-shell finite element method has the highest precision, and can predict the failure modes accurately. The research can also be regarded as a design reference for similar structures.