The accelerator C-80 for proton therapy of eye is under construction in B.P. Konstantinov PNPI. As a part of this project the protons beam delivery system with energies near 60 MeV was designed. The requirements to the beam characteristics were defined. We analyzed the beam delivery system and beam characteristics in Monte Carlo based system Geant4. The most accurate model of the description of physical processes was defined. Several variants of the system based on these models were calculated.