The motion of a small particle in a binary system where the radiation pressure is not negligible is considered. The photogravitational three-body problem is used as a model of formation of a disc by accretion. The author generalizes the method of \textit{Paczyńsky} [Astrophys. J. 216, 822 (1977)] which was applied to the family simple periodic orbits of a test particle in the cassical circular three-body problem. It turns out to be a good approximation to the streamlines in an accretion disc with very small gas pressure and viscosity. It is found that in the generalized model inclusion of radiation pressure may significally change the size and the shape of the disc. The increase of the radiation pressure force of the accreting star causes the decrease of the accreation disc, the radiation pressure force of the mass loosing star the increase of the disc size as much as 20\%.