The present invention discloses a method of online updating of urban rail transit signals, applicable to a scenario in which new and old positioning equipment coexist when signals of an existing line are disassembled, the method comprising: obtaining the position of a train based on said cross-induction loop, and obtaining the position of a train based on said transponder; recording the true position of the train when it passes through each crossing point of the cross-induction loop through on-board ATP, and the non-true position of the train based on the on-board speed measuring equipment and transponder; calculating the positioning error of the train based on said true position and non-true position; maintaining normal operation of the train using the position data obtained from the transponder; and inputting the train's operating data to maintain normal operation. non-true position of the train; calculating the positioning error of the transponder when passing through each cross induction loop crossing based on said true position and non-true position; using the position obtained by the transponder to maintain the normal operation of the train; inputting the operation data of the train into a neural network model to obtain the positioning error; and compensating the position of the train obtained by the transponder by using the positioning error. The present invention utilizes the old positioning device to improve the positioning accuracy of the new positioning device.