The densitometer was designed and fabricated with the underlying principle of gamma () ray attenuation produced on passing a collimated beam of monochromatic gamma radiation through any material. After standardization, the gamma ray attenuation coefficient (μ) was calculated to determine changes in densities as a function of temperature of Sb and Bi in solid phase. The density of Sb and Bi at room temperature are 6.697x103 Kgm-3 and 9.79x103 Kgm-3, and their melting points are 903.78 K and 544.7 K respectively. The measurements were conducted below melting point. The experimental results are in reasonable agreement with published data and may be used as reference data on variation of densities at various temperatures of solids.