Based on the transfer-matrix method, we have investigated the spin polarized transport properties of the electrons through ballistic graphene-based quantum tunneling junction with the Rashba spin–orbit interaction (RSOI). It is found that the spin-dependent conductance as well as the spin polarization rate oscillates with the RSOI strength λ R and the energy E of the incident electron. The oscillation features of the spin polarization rate and the conductance can be tuned largely by the RSOI for λ R ⪡E, while for λ R ≥E they are almost independent of the RSOI. These phenomena are essentially different from those found in conventional double tunneling junction.