Atmospheric pressure plasmas with microwave excitations were successfully produced in dielectric barrier micro plasmas employing N-2, Ar, or He gas. N-2 optical emissions of the second positive system were measured for evaluating the gas temperature. The gas temperatures of the plasmas could be much less than 1000 K. Blackbody emissions were measured, by Fourier transform infrared spectrometer for evaluating the electrode temperature. Temperatures of both the gas and electrode were evaluated by fitting. the experimental results with calculations. The gas temperature in the N-2 plasma was notably increased with the discharge time as compared with those in Ar and He plasmas. It was found that the pulsed discharge and the water-cooled electrode were effective for reducing the gas temperature. The pulsed discharge decreased the gas temperature from 900 to 600 K, and the water-cooled electrode decreased the gas temperature by more. than 200 K. Controlling the temperature of the electrodes was the most effective technique to reduce the gas temperature, because the gas temperature was in equilibrium with the electrode temperature. © 2005 American Vacuum Society.