A power operated valve for controlling fluid flow is provided with a fail-safe device responsive to failure of the power supply to the valve to shut-off fluid flow. A valve member is coupled to linear actuator for movement towards and away from a closed position for controlling fluid flow through the valve. The linear actuator is held in a control position by the fail-safe device for normal operation of the valve with the power supply on. The fail-safe device responds to failure of the power supply to release the linear actuator. When the linear actuator is released, energy stored n a spring while the linear actuator was held in the control position is released and biases the linear actuator away from the control position causing the valve member to move to the closed position to shut-off fluid flow.