We study the robust finite‐time leader–follower output consensus problems for second‐order multiagent systems (MASs) with mismatched disturbances. For mismatched disturbance, the mismatched disturbance observer is used for each follower to estimate the mismatched disturbance in finite time. Then a backstepping control protocol is constructed via Lyapunov finite‐time stability theorem, and we can prove that the output consensus tracking with strong robustness can be reached for the considered MAS in finite time if the communication topology includes a directed spanning tree, where the leader is the root. Finally, we use two simulation examples to illustrate the correctness of the theoretical results.