In order to study the universal theory of incoherently coupled spatial solitons pairs in photorefractive crystals, the theory of incoherently coupled soliton pairs based on the one-photon photorefractive effect is established in one-photon photovoltaic photorefractive crystals illuminated by e-polarized incoherent uniform back-ground irradiation with a divider resistance under steady-state conditions. The numerical results show that these soliton pairs can be established by two carrier beams which share the same polarization, wavelength and are mutually incoherent. When these incoherent coupled soliton pairs propagate together, two components can propagate stably in photorefractive crystal. The 14 kinds of incoherently coupled spatial soliton pairs can be obtained from this theory by adjusting the value of the divider resistance, e-polarized back-ground irradiation, the biased electric field and photovoltaic electric field. The proposed studies have great significance to the photorefractive spatial soliton theory system.