The variants of time synchronization of modern surveillance multilateration (MLAT) systems with usage of various internal and external sources of a single time are considered. The results of a comparative analysis of the features of construction and circuitry implementation of time synchronization of MLAT are presented. These results are based on the use of synchronization of separated receiving sensors and a shared server for receiving, combining, and joint processing of received sensor signals emitted by the aircraft, with subsequent evaluation of position and parameters of movement of the detected aircrafts. The main disadvantages and advantages of the presented variants of time synchronization of MLAT are shown. The usage of additional channel for receiving and processing of TV signals emitted by local TV centers, which can improve the quality of synchronization, increase the reliability, as well as the accuracy characteristics of MLAT is proposed.