Abstract: A optical chip includes: an optical splitter, configured to receive a first electromagnetic wave signal, and divide the first electromagnetic wave signal into two electromagnetic wave signals for output; and a first interferometer and a second interferometer, where the optical splitter, the first interferometer, and the second interferometer are sequentially coupled, and the first interferometer and the second interferometer are configured to receive one of the two electromagnetic wave signals, so that the one electromagnetic wave signal is interfered twice, to output a plurality of second electromagnetic wave signals. The other one of the two electromagnetic wave signals is output as a third electromagnetic wave signal, and the second electromagnetic wave signal and the third electromagnetic wave signal may be used to obtain wavelength information of the first electromagnetic wave signal through optical-electrical conversion. A wavelength measurement system is further provided.