The present invention discloses a fiber amplifier, a fabricating method thereof, and a fiber communication system. The fiber amplifier includes at least a pump laser, at least a gain medium and at least an integrated optical component. The integrated optical component includes multiple optical input/output ports, and the optical input/output ports are connected to the pump laser or gain medium directly or indirectly. The present invention may better address problems of unstable performance and difficulty in reducing the size of components in the prior art where fiber amplifiers are formed by a number of discrete components with many fiber fusion splices. In addition, the present invention may reduce the production complexity and costs of fiber amplifiers, and improve the productivity of fiber amplifiers.