Abstract: The present invention provides, in at least one embodiment, a system and method for power control of lasers. The system includes a device's control signal fed into a laser. The laser can be a master oscillator power amplifier (MOPA) fiber laser. The device includes an equivalent model circuit representing at least one parameter of the laser, such as the gain fiber inversion in the power amplifier. The device measures the power at the equivalent model circuit. Then, the device uses its feedback signal to control and/or adjust the output power control signal fed into the laser based on the measured power. By controlling the power fed into the laser, the laser can be operated at much lower frequencies while keeping the laser power within acceptable limits.