Midinfrared spectra of the OH+-He/Ne open-shell ionic complexes have been recorded by photofragmentation spectroscopy in a tandem mass spectrometer. The nu(1) vibration (OH stretch) and its combination band with the intermolecular bending vibration (nu(1) + nu(b)) have been observed for both complexes at the level of rotational resolution. The analysis of the spectra shows that both complexes have a linear proton-bound structure in their (3)Sigma(-) electronic ground states, with intermolecular center-of-mass separations of 2.60 and 2.65 Angstrom for OH+-He and OH+-Ne, respectively. The nu(1) vibrational origins are redshifted by 66.3 and 169.9 cm(-1) with respect to the corresponding monomer transition indicating that the intermolecular interaction increases upon nu(1) excitation. The fine structure of the nu(1) ((3)Sigma(-)<--(3)Sigma(-)) and nu(1) + nu(b) ((3)Pi<--(3)Sigma(-)) transitions arising from electron spin and vibrational angular momentum of nu(b) have been analyzed in terms of a semirigid Hamiltonian including spin-spin, spin-rotation, and l-type doubling interaction terms. The molecular parameters extracted from the molecular constants provide valuable information on the radial and angular part of the intermolecular potential-energy surface in each considered vibrational state. The intermolecular interaction in OH+-Ne is stronger than in OH+-He, mainly due to the larger polarizability of the rare-gas atom.