A thermal accelerometer was developed and evaluated. The presented device was fabricated directly on an organic substrate, which ensures a high level of thermal isolation, while also facilitating direct electrical communication to the macroworld. The role of the seismic mass was utilized by a fluid (water), which was confined in a tank adjusted on the sensor surface. Acceleration quantification is achieved by the monitoring of the cooling effect on the heating element. A sensor signal of 32mV for an acceleration of 1g was obtained.