The photon interaction cross-section of thin uniform multiple foil attenuators (Ag, Cu, Fe) were determined in the energy range 0.360MeV-1.33MeV with a view to study the effect of atomic numbers and photon energy on absorption coefficient under collimated narrow beam geometry set-up. The measurements were taken for the linear absorption coefficient (μ), mass absorption coefficient (μ/ρ) and total photon interaction cross-section of different elemental solids of uniform thickness 0.15 cm, on NaI(Tl) detector using scintillation counter. The result shows that; as atomic number increases linear attenuation coefficient (μ), mass attenuation coefficient (μ/ρ) and total σTotal photon interaction cross-section understudy decreases with increase in Photon energy.