The sequence of tasks is vital to the development of any project. Theorder of tasks is influenced by the information flow among them. Thedependency structure matrix (DSM) can be used to model informationflow. However, the information used by the DSM, including task duration,time required for communication, and task overlap, can have uncertainvalues. The aim of this paper is to analyze the effect of uncertaintyon the scheduling of tasks using the DSM. Monte Carlo Simulation isapplied to represent uncertainty in time estimates for projects usingDSM. Conventional project duration, normal project duration withcommunication times, and normal project duration containing naturaloverlapping were considered for project time estimations. Severaldistribution functions were used to represent the uncertainty. It isconcluded that project duration has normal distribution behavior thatis independent of the type of input parameter distribution functions;that mean values of the input parameters give a good estimation ofmean project duration; that interval and inner interval arithmeticgive overestimation and underestimation of project duration timesrespectively.