Electron temperatures obtained from the slope of the electron energy probability function (EEPF) at the floating potential were compared with those measured by the floating harmonics method in various electron distributions. Basically, these two types of the electron temperatures should be same in a Maxwellian electron distribution. As expected, discrepancies were observed between them in cases of non-Maxwellian distribution. In this study, the second and third harmonics of probe current were used to obtain the electron temperature in non-Maxwellian distribution. The experimental results were shown that the electron temperature obtained using this method was in good agreement with the electron temperature from the slope of the EEPF at floating potential, regardless of the electron distribution.