<p>Provided are a method and device for realizing clock recovery. The method includes:acquiring adjustment information about each frame of service layer data during the process of asynchronously demapping client layer data from the service layer data; adjusting a decimal frequency division factor determined by the total number of bytes of each frame of the service layer data and the number of bytes occupied by the client layer data according to the adjustment information;and, after performing decimal frequency division on the service layer clock according to the decimal frequency division factor, taking same as the reference clock of a phase locked loop, and recovering the client layer clock by means of the phase locked loop.The present invention can improve the capability of transparent transmission and cascading of the clock.</p>
