Title Bi-Level Unit Commitment Considering Virtual Power Plants and Demand Response Programs Using Information Gap Decision Theory Type of Research Article Keywords Virtual Power Plants, Demand Response Programms, Smart Grids, Unit Commitment, Bi-Level Programming, Information Gap Decision Abstract The integration of the distributed energy resources into a single entity can do with virtual power plants. VPP is a cluster of dispatchable and non- dispatchable resource with flexible loads which distributed in allover the grid that aggregated and acts as a unique power plant. Flexible load is able to change the consumption so demand response program is applied to use them to improvement of the power system performance. Virtual power plant generation has uncertainty and it make hard to schedule the VPP. To deal this matter Information gap decision theory hint us to optimal schedule of the VPP. To show the effects of VPP and DRP on power system operation cost a bi-level unit commitment with regard the VPPs and DRP is solved in modified IEEE 24 bus reliability test system. Results in presence of VPP and DRP in both IGDT strategies are compared with disregard VPP and DRP and effectiveness of the proposed model is reflected. Researchers Yousef Babaei Shahmaras (First Researcher)، Javad Salehi (Second Researcher)، NAVID TAGHIZADEGAN KALANTARI (Third Researcher)