The three-dimensional standard vibrator based on leaf-spring-type decoupling device contains a base set with three single-dimensional vibrators (along X, Y and Z axes, respectively) and a three-dimensional vibration platform. The X axis vibrator is connected with the three-dimensional vibration platform through X axis decoupling device, the Y axis vibrator is connected with the three-dimensional vibration platform through Y axis decoupling device, and the Z axis vibrator is connected with the three-dimensional vibration platform through Z axis decoupling device. The properties of the three-dimensional vibrator are as follow. X axis decoupling device, Y axis decoupling device and Z axis decoupling device are all comprised of supporting-spring units. Each of the supporting-spring units contains a pair of leaf springs mounted parallel with each other and the first and second connecting components mounted on the two edges of the leaf springs.