Single- layer optical film prepared by electron beam evaporation possesses remarkable columnar structure. The variation of its internal film refractive index is large, so the induced volume scattering phenomenon is relatively obvious. Based on the first-order electromagnetic perturbation theory, the volume scattering theory model of single- layer optical film is established. The effects on volume scattering caused by layer thickness, polarization state of incident light, columnar structure factor and inhomogeneity are analyzed. For optical films with pure columnar structure, the variation law between the volume angle resolved scattering (ARS) of single-layer hafnium oxide (HfO2) thin films prepared by electron beam evaporation and the layer thickness is established. The ARS magnitude of volume scattering for pure columnar HfO2 films is similar to that of the completely uncorrelated surface scattering model. Within a certain range of film thickness, the ARS value of volume scattering increases with the increase of film thickness. For inhomogeneous thin films, the ARS value of volume scattering increases with the increase of film thickness when the inhomogeneity is constant. When the layer thickness is constant, the ARS value of volume scattering will decrease the increase of the absolute value of the inhomogeneity.