The invention provides a three-axis
accelerometer, comprising a substrate, a
mass detection block, a support base, and at least a first comb-shaped
capacitor group. The support base is fixed on the substrate. The
mass detection block is suspended on the surface of the support base in an asymmetrical manner through springs which are arranged oppositely. The substrate is provided with at least two electrodes which are opposite to each other. The electrodes are respectively corresponding to the side of the
mass detection block where the mass is relatively large and the side where mass is relatively low. The electrodes are used to form a
capacitor with the mass detection block. The first comb-shaped
capacitor group is disposed between the line where the springs are in and the electrodes. When the
accelerometer has acceleration speed parallel to the first direction of the substrate plane, the
capacitance of the first comb-shaped capacitor group changes. The
accelerometer is advantaged in that the first comb-shaped capacitor group is disposed between the line where the springs are in and the electrodes, so the
vertical distance from the
electrode to the line where the springs are in is increased, thereby improving sensitivity of the three-axis accelerometer on a direction of vertical to the substrate plane, so that a
high sensitive accelerometer is provided.