In this report, we present an ecological Agent Simulation System, which simulates the interactions between ecological agents and shows the statistics of simulation results. We discuss how we design and implement it using Object-oriented analysis, design, and programming. The design phase illustrates how we apply the concepts of Object-oriented methodology to develop this software application--the Agent Simulation System. The implementation phase demonstrates the programming process by using an Object-oriented language (C++) and Software Development Kit (Visual C++). We show the simulation results with two simulation examples and analyze the statistics. We conclude by listing some advantages of Object-oriented we experienced from this project and suggest further work.