An experimental study has been conducted to evaluate the effects Of CO2 addition on thermal behavior in oxygen-enriched hydrogen flame. Experiments were performed on flames stabilized by a co-flow swirl burner, which was mounted on top of the furnace. Several different oxidizer compositions were prepared by volumetrically replacing N-2 by CO2. In a steady state, the total as well as radiative heat flux from the flame to the wall of furnace has been measured using a heat flux meter. Temperature distribution in furnace has been also measured and compared. By increasing CO2 proportion in the oxidizer, the convection became to play a more significant role rather than radiation due to heat blockage effect. Overall temperature in the furnace was seen to decrease, while the total heat flux has increased.