Molybdenum oxide (MoOx), owing to its large work function, is an attractive material for hole-selective contact (HSC) in crystalline Si-based solar cells because it introduces upward band bending when constructed into a heterojunction silicon (SHJ) cell structure. In this study, we fabricated a p-type SHJ bifacial solar cell with a rear-side MoOx HSC layer. The MoOx thickness was varied from 3 to 15 nm, and cell bifaciality was addressed. The cell efficiency decreased when the MoOx thickness was increased to more than 5 nm. A maximum front-side cell efficiency of 17.89% was obtained, while the rear efficiency was 16.02%, which shows the potential of MoOx for p-type bifacial cell fabrication. The maximum open circuit voltage (VOC) and short circuit current density (JSC) for the front side were 635.71 mV and 35.57 mA/cm2, respectively, while the rear side VOC and JSC were 623.62 mV and 32.67 mA/cm2, respectively. The interfacial properties were carefully studied as a function of MoOx thickness. This work demonstrates the importance of selecting MoOx for p-type crystalline silicon (c-Si) solar cells.