The invention provides a monolithic integrated three-axis 
accelerometer and a manufacturing method thereof so as to solve the defects in structure and 
manufacturing technology of the existing structural 
capacitive accelerometer. Three 
layers of 
metal Al thin films are deposited in the direction of an axis Z so as to form a comb pair sensitive 
electrode; four 
layers of 
metal Al / SiO2 thin films are deposited in the directions of an axis X and an axis Y so as to form comb pair sensitive electrodes, and the accelerations of the three axis directions are detected simultaneously by a single integrated structure. The 
accelerometer and the manufacturing method thereof have the following positive technical effects: the 
interconnection stray 
capacitance among accelerator devices in three axis directions is lowered remarkably, and high detection accuracy and lower 
noise performance are realized; since the 
accelerometer is provided with the multiple 
metal layers, compared with a microaccelerometer manufactured from the same material, namely 
polycrystalline silicon, the accelerometer is more flexible in wiring; a foldable beam is used in the structure of the accelerometer, so that the own stress of the accelerometer is released better, and therefore the influence of the stress on the 
system can be reduced effectively.