Provided is an apparatus for an optical clock extraction, which is capable of providing high optical amplification rate and more efficient noise cancellation by using a Fabry-Perot (FP) filter and an optical amplifier. In the apparatus, an optical circulator changes a direction of an inputted optical signal. The FP filter extracts different frequency components existing on a spectrum of the inputted optical signal and being spaced apart by a clock frequency, removes noise from a reflected and amplified optical signal, and transmits the resulting signal to the optical circulator. An optical amplifier performs a primary amplification to equalize two different frequency components outputted from the filter, and performs a secondary amplification on an optical signal reflected and fed back thereto. A reflector reflects the primarily-amplified optical signal to the optical amplifier.