The invention relates to an optical link-based remote in-service inspection system for a reactor pressure vessel. The system comprises a control and communication device, an analysis device, an in-island interface box arranged in an equipment inspection zone in a nuclear island, a first out-of-island interface box arranged in a main control zone out of the nuclear island and a second out-of-island interface box arranged in a data analysis zone out of the nuclear island, wherein an in-island equipment group is in phase signal connection with the in-island interface box, an out-of-island equipment group is connected with the first out-of-island interface box, the analysis device is connected with the second out-of-island interface box, the in-island interface box is connected with the first out-of-island interface box through optical cable-phase signals, and the first out-of-island interface box is connected with the second out-of-island interface box through signal line-phase signals. According to the invention, the unified optical link is employed to realize control and communication of a variety of signals in and out of the nuclear island, and a unified signal link is adopted to realize signal control and communication between the control zone and the analysis zone out of the nuclear island; and the optical link-based remote in-service inspection system for the reactor pressure vessel has the advantages of simple structure and reliable and convenient usage.