In this work, the influences of Ba0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) addition on phase, microstructure, and thermoelectric properties of Ca3Co4O9 (CCO) were investigated. (1-x)CCO-(x)BCZT ceramics where x = 0, 0.003, 0.005, and 0.010 were fabricated successfully via a conventional solid-state sintering at 1,223 K for 24 hrs. The substitution of BCZT introduced the chemical defects (V''Co, V'''Co, V''Ca) in CCO ceramic, which increased charge carrier concentration and enhanced the electrical conductivity. The presence of Co3+ improved the Seebeck coefficients of CCO ceramic. The thermal conductivity of CCO ceramic decreased when BCZT was added. The addition of BCZT at x = 0.010 promoted the highest thermoelectric power factor (PF~235 mW/mK2), and the highest figure of merit (ZT~0.5) at 800 K, which present this ceramic an alternative p-type oxide thermoelectric for a high-temperature thermoelectric device.