During non-line-of-sight ultraviolet (UV) communication, as the elevation angle of the transmitter decreases, more UV photons can be scattered by the ground and reach the receiver, and those photons are important components of the received signals. In this paper, a new, to the best of our knowledge, non-line-of-sight noncoplanar UV scattering transmission model taking into account the UV rough surface scattering characteristics is proposed based on the theory of non-line-of-sight multiple scattering UV light transmission and the Monte Carlo method and Kirchhoff's dwell phase method. The proposed model is validated by experiment. Simulation and experiment show that the energy of UV light is mainly concentrated in the direction of mirror reflection after being scattered by the concrete floor, and the energy gets stronger as it gets closer to the mirror reflection direction. In the case of small elevation angle, the photon energy scattered by the ground and received by the receiver must be considered. The path loss obtained by the improved model better fits with experiment.