It is demonstrated that an ultranarrow linewidth laser is recovered after transfer through a 100 km fiber link. The fiber link consists of two 50 km spolled fibers cascaded by a repeater station where a transceiver laser is phase-locked to the transferred light of the 50 km fiber with tracking precision of 3.5×10－19. To maintain the high spectral purity, two fiber noise compensation modules are employed to compensate for the fiber-induced phase noise in each 50 km fiber. The cascaded scheme enables a large dynamic range for the noise compensation. The fractional frequency instability for the stabilized 100 km fiber is 5.9×10－17 at 1 s averaging time, reaching 6.8×10－19 at 10 000 s. The ultranarrow linewidth laser is recovered at the remote end of the 100 km fiber with additional linewidth of 1 mHz.