A monolithic accelerometric transducer comprises a fixed part, two mobile mass parts and a resonator having ends fastened to said mobile parts, a flexible frame around the two mobile parts, and two connecting members connecting the frame to the second mobile part and to the fixed part. The frame provides a mechanical filter between the resonator and the fixed part which is not affected by the vibrations of the resonator. The quality factor Q of the resonator is not degraded and the measurement provided by the transducer is more accurate. In a differential output accelerometer, the position of the transducer is deduced from that of another, identical transducer by rotation of 180.degree. about an axis parallel to the resonator, the fixed parts of the transducers being fastened together.