BiFeO₃ thin films have been grown on Pt/Ti/SiO₂/Si substrates with pulsed laser deposition using Au as the top electrode. The resistive switching property of the Au/BiFeO₃/Pt stack has been significantly improved by carefully tuning the oxygen pressure during the growth, and a large switching ratio of ∼4500 has been achieved. The deposition pressure modifies the concentration of oxygen vacancies and the rectifying behavior of the Au/BiFeO₃ junction, and consequently influences the resistive switching behavior of the whole stack. The switching takes place homogeneously over the entire electrode, and shows a long-term retention.