Determination of seismic performance for a structure is one of the most important topics that researchers have attended to. Most of regulations regarding performance-based design, introduce the drift as a criterion to determine global seismic performance of the structure. Recently, pushover analysis has widely been adopted as the primary tool for nonlinear analysis because of its simplicity and facility compared with dynamic procedures. The main objective of this research is to develop some relations to estimate damage to Reinforced Concrete Moment Resisting Frames (RCMRFs) based on drift criterion resulting from pushover analysis. For this purpose, by employing the Park-Ang damage index, damage analysis is performed on several frames subjected to various earthquake records. By comparing the amounts of damage and drift and evaluating correlation between two sets, some explicit damage functions are derived based on the pushover results. These functions can be applied to estimate the damage to the structures using a simple pushover analysis. The reliability of FEMA-273 acceptance limits on the drift criterion is discussed using the proposed drift based damage functions.