Advances in object-oriented (OO) technology and distributed computing generate distributed object oriented software systems. Choosing an efficient design of such software is multi-criteria decision problem. Performance is a key criterion that makes software developers be able to select the system that best fit their requirements and achieve longer design stability. Classical techniques of performance analysis are either unsuitable or unnatural to capture performance behavior of OO systems. In this paper, we present Performance-Based Model for Distributed OO software (DOOS) and a methodology to analyze and evaluate its performance. The new model evaluates the time cost of DOOS system considering the communication overheads while preserving the OO features such as encapsulations and inheritance.