The physicochemical properties of La_0.8Ca_0.2Nn_1−xCo_xO₃ nanopowders as a function of Co content (x) have been investigated. La_0.8Ca_0.2Nn_1−xCo_xO₃ nanopowders were synthesized by sol-gel method and morphologically and structurally well characterized by Scanning electron microscopic (SEM), Infrared spectroscopic (IR) and Raman spectroscopic techniques. IR spectra shows peak at around 600 cm⁻¹ attributed to the stretching mode of MnO₆ octahedral and peak at 700 cm⁻¹ assigned to La-Ca-O-Mn bending vibrations. Raman spectra indicate peaks at around 512 and 652 cm⁻¹ related to the Jahn-Teller octahedral distortions. The intensity of these peaks increases with increasing Co doping. The UV-visible spectra were measured in the frequency range of 200-800 nm and two energy gaps were found at 1.63 eV and 3.294 eV for x = 0, 0.1 and 0.3.