Abstract: Under the condition of small angle misalignment,the effecton output beam's near-field distribution of CO2 lasers with two-dimensional axisymmetric-fold combination cavity was ascertained after analyzing and simulating beams combination output based on the axis determination of misaligned plano-concave and concave-plano-concave cavity resonator.The results showed that at small angle misalignment,the effect on near-field within 4cm was un-conspicuous and the light intensity was still at Gaussian distribution,and that out of the 4cm area,the effect became obvious with the misalignment angle.These results showed that the effect on near-field with 4cm was more practically.