A general mechanism of large‐amplitude stabilization of the drift instability is investigated. For slab geometry, a drift‐wave potential of the form&phgr; = &PHgr; cos(kxx) cos(kyy+kzz−&ohgr;t)is used wherexis the direction of plasma density inhomogeneity andzis the direction of a uniform field. It is assumed thatkx∼ky≫kzand&ugr;i≪&ohgr;/kz≪&ugr;e. Studies of the exact guiding‐center particle trajectories in the drift‐wave potential show the existence of time‐average,y‐direction velocities whose magnitudes increase with the amplitude of the drift wave. As the wave grows, these velocities shift parts of the resonance region away from&ugr;z = &ohgr;/kzand finally into the bulk of the ion distribution. Thus, the original instability is stabilized by strong ion Landau damping. Stabilization will occur around the wave amplitude satisfying the condition,ckx&PHgr;/B=&ohgr;/ky.