A computer numerical control (CNC) servo drive system includes a controller, a driver, a co-connection circuit, a first servo motor and a second servo motor. Users input a control command through the controller. The driver is connected to the controller, converts the control command into a drive signal, and outputs the drive signal. The co-connection circuit is connected to the driver and transmits the drive signal. A sum of maximum current values of the first servo motor and the second servo motor is not greater than a maximum current value of the driver, such that the driver can simultaneously drive the first servo motor and the second servo motor for operation.