Large-aperture pulse compression gratings are needed by laser confinement fusion system. Tiled-grating made by holographic exposure is an important way to manufacture large aperture gratings. A method is proposed to align the gratings for the exposure system with wave aberration. In order to study the effect of the wave aberration on the characteristics of tiled-grating, the random wave fronts are used to simulate the tiled-gratings. The relationship between the distribution of far-field diffraction energy and the tiling-error is calculated. A grating of (150+150)×200 mm2 is made experimentally. The root-mean-square value of the tiling-error is 0.034λ and the peak to peak value is 0.110λ. The ± 1st diffraction wave fronts of the grating are used to calculate wave aberration of the exposure system. The minimum value of the tiling-error is simulated theoretically. The root-mean-square value of the error is 0.016λ and the peak to peak value is 0.105λ. The results show that the tiling-error is close to the simulated data. The far-field diffraction intensity can not be decreased obviously by the tiling-error. It is proved that the method proposed in this article is feasible.