This paper presents a thermal flow sensor based on the calorimetric principle realized by using low temperature co-fired ceramic (LTCC) technology, where the tapes and flow channel have been structured by laser machining. A standard configuration of a calorimetric sensor consists of a heater placed above the flow channel and temperature sensitive elements arranged symmetrically downstream and upstream. The temperature difference between temperature sensitive elements (at the upstream and downstream position) acts as a measure of flow velocity. The structure and the characteristic of the sensor are demonstrated.