A power-saving data scheduling system includes a period decision module for selecting a cycle having a shortest delay time as a discontinuous reception (DRX) cycle for each user from quality of service (QoS) requirements related to network services and channel conditions, and a start offset decision module for calculating the number of users in each of periods of the DRX cycle. In addition, a DRX-aware scheduling module is provided for extending the on period by increasing priority of the user and resetting an inactivity timer if a period required by the user's load is shorter than an off period. Optimal DRX parameters and DRX-aware scheduling are used to resolve the existing issues that the channel conditions, system load and QoS are not taken into consideration when the DRX parameters are determined. Moreover, a power-saving data scheduling method is also provided.