The influences of cross-cracks on the jointed rock mass failure modes and mechanical properties were studied. The brittle jointed rock mass specimens with cross-cracks were simulated by similar material. There were 20 groups of jointed rock mass similar material specimens in which the angle between main crack and loading direction and the angle between main crack and secondary crack were taken as changing parameters. The specimens of jointed rock mass similar material were tested to obtain the influences of cross-cracks on jointed rock mass failure modes and mechanical properties. The test results show that when the angles between main crack and loading direction are 0°and 90°

the failure modes of specimens are mostly shear type failure propagating from the secondary crack; when the angles between main crack and loading direction are 30°and 45°

the failure modes of specimens are mostly shear type failure propagating from the main crack; when the main cracks are at same angle

the strength of most jointed rock mass similar material specimens with cross-cracks is higher than the strength of specimens with single crack; the post-peak stress-strain curve descending slopes of most jointed rock mass similar material specimens with cross-cracks are steeper than the slopes of specimens with single crack; the specimens have low strength when the angle between main crack and secondary crack is about 45°

and the specimens have high strength when the angles between main crack and secondary crack are about 30° or 90°.