Method, system and device for sending time synchronization information

The embodiment of the invention discloses a method for sending time synchronization information, comprising the following steps: receiving first time synchronization information from an optical line terminal (OLT), wherein the first time synchronization information is the local time synchronization information of the OLT, and comprises 1 pulse per second (1PPS) signals and time of day (ToD) signals; calculating the average period of the multiple continuous 1PPS signals in the first time synchronization information, and regulating the period of the next 1PPS signal or the next group of 1PPS signals to be the average period; and configuring the ToD signals and the 1PPS signals which are subjected to the period regulation into second time synchronization information and sending the second time synchronization information to a user terminal device so as to carry out time synchronization processing for the user terminal device. The embodiment of the invention also provides a system and device for sending time synchronization information.