The causes and characteristics of the intracavity aberrations in unstable thin-disk laser are introduced. And an active correction technique is proposed to correct the aberration in the cavity by the combination of defocused and two-dimensional(2D)deformation mirrors. Based on the simulation and optimization design, the dynamic range of the defocus correction deformation mirror can reaches to 18.52 μm (peak-valley value). The static surface of the 2D mirror is less than 0.04 μm (root mean square error), the single driver dynamic range greater than 6 μm (peak-valley value), and the coupling coefficient is in the range of 30% to 35%. These two kinds of deformable mirrors are placed in the laser cavity for active closed-loop correction. The beam quality was improved to 19.5 after defocusing correction, and then improved to 6.5 after 2D deformable mirror correction. The wavefront aberration is reduced from 1.504 μm (root mean square error) to 0.185 μm (root mean square error). The beam quality increased by 3 times and the root mean square error increased by 8.1 times. Experimental results show that the combined correction mode can effectively improve the intracavity aberration in unstable thin-film laser, and its technical route is feasible.