We report the structural and electrical properties of the Co3-xMnxO4 (CMO) with x = 0.1 to 1.0 ceramics, synthesized by conventional solid state reaction technique. These ceramics have been characterized at room temperature by the powder X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. XRD and FTIR spectra reveal the formation of polycrystalline single-phase with cubic spinel structure. The observed room temperature dc conductivity increases with the substitution of Mn in CMO and revealed the semiconducting nature of these ceramics, due to the hopping between the cations with the different valence states at the octahedral sites. The ac conductivity was estimated from the observed dielectric data as a function of frequency at different temperature. The estimated ac conductivity was explained through the small polaron tunneling (SPT) and correlated barrier hopping (CBH) model. The dispersion of ac conductivity has been estimated in terms of temperature dependent frequency exponent s(T), which varies with temperature and explained using SPT and CBH model.