In this study, a new method for the measurement of figure of merit, Z, of a thermoelectric module has been introduced. The new method depends on the measurement of thermoemf, voltage and hot side temperature of the module. A new microcontroller test system has been designed and realized using this new method. Then, the realized new test system has been used to measure the Z of a standard thermoelectric module (Melcor CP 1.4-127-10L). Measured values have been found to be in close range with the manufacturer's catalog data.