The invention relates to the technical field of nano-positioning, measuring and machining devices, in more particularly to a three-axis cutter servo device based on a compliant parallel mechanism. Thethree-axis cutter servo device comprises outer side fixing bases, an inner side fixing base, uniaxial nano-positioning platforms and a three-axis end actuator, wherein the uniaxial nano-positioning platforms and the three-axis end actuator transfer motion through compliant hinges and flexible rod pieces. The three-axis end actuator is connected with a cutter and provided with a capacitive sensor,and the capacitive sensor is connected with a controller. The output end of the controller is connected with a piezoelectric ceramic driver, the piezoelectric ceramic driver is connected to the inputends of the uniaxial nano-positioning platforms, and the three-axis end actuator is connected to the output ends of the three uniaxial nano-positioning platforms. According to the three-axis cutter servo device based on the compliant parallel mechanism, nanoscale linear displacement of the three-axis end actuator can be output, meanwhile, end output displacement is directly measured through the sensor, feedback control is conducted, and the three-axis cutter servo device has high stiffness, high precision, the high bandwidth, the large stroke, the high speed, high acceleration, the large bearing capacity and excellent decoupling performance.