This paper presents three methods implemented in the activity-based construction modeling and simulation (ABC) system for validating a construction simulation. The first method reports a simulation experiment in the chronological order so that the user can examine the operating sequence of the model. The second method provides the summary information of total operating counts and mean durations of all activities in the model so that the user can evaluate whether all activities have been correctly executed during simulation. The third method produces the cyclic report of a selected resource entity so that the user can examine whether the entity is moving in the correct logical and chronological order during simulation. The three methods can effectively assist the user in debugging a simulation model so as to assure that the simulation is correctly conducted. A road paving process is employed to illustrate these methods.