In this paper, we study the containment control problem of heterogeneous linear multi-agent systems under directed topology based on output regulation framework and using output feedback control. Motivated by leader-follower output regulation problems, the leaders are assumed to be exosystems with identical dynamics. In controller design approach for each follower, we utilize a distributed dynamic output feedback control scheme. To achieve the objective of this work we utilize the containment error, which enables us to consider more than one leader in output regulation framework and to use output regulation techniques with some modifications to solve the containment problem. Finally, the validity of theoretical results are demonstrated through an example.