A process for fabricating a capacitance type tri-axial accelerometer comprises of preparing a wafer having an upper layer, an intermediate layer and a lower layer, etching the lower layer of the wafer to form an isolated proof mass having a core and four segments extending from the core, etching the upper layer of the wafer to form a suspension and four separating plates, etching away a portion of the intermediate layer located between the four segments of the proof mass and the plates of the upper layer, and disposing an electrical conducting means to pass through the intermediate layer from the suspension to the core of the proof mass.