Provided is a hybrid optical amplifier using a gain-clamped semiconductor optical amplifier enabling Raman amplification. The hybrid optical amplifier comprises a spool of optical fiber used as transmission line in the optical communication, a GCSOA amplifying optical signal input via the optical fiber and generating a self-oscillation laser beam for gain-clamping through the gain medium, and a backward pumping Raman optical amplifier inducing Raman amplification by emitting the self-oscillation laser beam generated by the GCSOA into the optical fiber. Therefore, the Raman amplification can be obtained with a relatively simple structure using the GCSOA.