This work reports a <inline-formula> <tex-math notation="LaTeX">\beta </tex-math></inline-formula>-Ga 2 O 3 double-barrier Schottky barrier diode (DBSBD) with both low turn-on voltage and low reverse leakage current by using Ni and PtO x as the anode electrode. The barrier height of PtO x -based diode can be effectively modulated from 1.26 to 1.62 eV by adjusting oxygen pressure during sputtering processes. Combining the maximum work function of PtO x electrode with the optimization of the electrode ratio of Ni and PtO x , the DBSBD with an electrode diameter ratio of <inline-formula> <tex-math notation="LaTeX">\text{D}_{\text {Ni}} /\text{D}_{\text {PtOx}}= {75}/{150} \mu \text{m} </tex-math></inline-formula> not only exhibits a high forward current of 470.9 A/cm 2 (at 3.5 V), a low on-resistance of 4.1 <inline-formula> <tex-math notation="LaTeX">\text{m}\Omega ~\cdot </tex-math></inline-formula>cm 2 and a low turn-on voltage of 1.13 V, but also possesses a relatively low reverse leakage current of <inline-formula> <tex-math notation="LaTeX">{1.2}\times {10}^{-{7}} </tex-math></inline-formula> A/cm 2 (at −100 V), which is more than one order of magnitude lower than that of the Ni-SBD. Silvaco TCAD simulation reveals that such optimization can be attributed to the suppression of edge leakage current due to the double-barrier contact. Therefore, the strategy of double-barrier design can balance the forward and reverse characteristics in SBD, providing a new device structure for advanced power electronics.