In this paper, a multi-objective particle swarm optimization (PSO) algorithm is implemented to unveil trade-off margins of the CMOS two-stage operational amplifier (op-amp). Power dissipation, DC gain, equivalent input referred noise, area, slew rate, unity gain frequency (UGF) are used as objectives. Width and length of the gate of MOSFETS are free parameters. Simulation results revealed the design trade-off margins of the two-stage op-amp as expected theoretically.