The maladjustment of unstable-stable hybrid resonator is studied theoretically.When the parametersoutput mirror of hybrid resonator areis changedadjusted,we calculate the loss of the lowest-order mode with Fox-Li method. The results show that the resonator is stable in stable direction,and unstable in unstable direction,especially when the output mirror is rotated or moved in unstable direction. The off-axis unstable resonator is more stable than the symmetrical unstable resonator. With the maladjustment characteristic of the hybrid resonator,we can improve the Q-switch scheme and we prove the application of AOM in positive unstable-stable hybrid resonator theoretically.