There is disclosed a method and system for controlling network timing precision of a seismic collector, and a terminal device. The method includes: using an interrupt mode to transmit a data packet; calculating an optimal network delay; and correcting a transmission error in a network timing process according to the optimal network delay, after which the physical layer of a server receives the data packet and sends the data from the physical layer of the server to the application layer of the server using the interrupt mode thereby timing the data packet.