A micromachined omnibearing level posture sensor has been proposed in this paper. The octagonal sensing organ fabricated by the micromachined technique is used to sense the omnibearing level posture; the signal processing circuit is composed of a pre signal circuit and a digital circuit to pick up the voltage signal and synthesize the omnibearing signal as well as compensate the resolution of the omnibearing tile signal. It is testified that the resolution is less than 0.1°, the scope of azimuth is 360°, and the scope of tile angle is 20°. The sensor is not only small in size but also is compact and simple in fabrication. It is good in sensitive organ’s output consistency, and suitable for mass production.