This study presents the design and application of an integrated control logic architecture for a 300BPD ES-SAGD(Expanding Solvent Steam-Assisted Gravity Drainage) demonstration plant, aimed at ensuring operational stability and efficiency. With the global expansion of unconventional oil resource development, ES-SAGD is recognized as a technology advantageous for reducing viscosity and improving energy efficiency compared to conventional SAGD. In this research, the plant process was analyzed to identify key control variables and potential risk factors, and a control logic structure integrating supervisory and unit-level control was designed. The stability and reliability of the control logic were validated through Hardware-in-the-Loop Simulation(HILS) and field implementation. The findings are expected to contribute to safer operation, reduced commissioning periods, and enhanced automation in future oil sands demonstration and commercial plants.