The invention discloses a clock recovery and adaptive equalizer combination device and method in coherent light communication, relates to the technical field of coherent light communication, and adopts a new equalizer structure and algorithm to realize clock recovery and adaptive equalization at the same time. Specifically, a two-stage real number equalization structure and a second-stage adaptivecoefficient are adopted to calculate a timing error so as to realize clock recovery, polarization demultiplexing and dispersion compensation. According to the structure, an independent clock recoverymodule is omitted, compared with a traditional structure, the calculation complexity is reduced, the clock recovery accuracy is improved, and the tolerance to IQ data imbalance of a receiving end isimproved. The two-stage equalization of the structure adopts real number equalization, so that the IQ two paths of data are not combined together any more in the equalization process, and the problemthat the system performance is greatly influenced under the condition that IQ has time delay can be effectively solved.