The present invention discloses a method and system for tracking signaling in an automatically switched optical network (ASON), wherein the method comprises a step of setting a signaling tracking filtering condition for a corresponding signaling tracking task, and the following steps that: an ASON node collects and reports a received or sent signaling message when there exists a task tracking request; and when the reported signaling message is determined meeting the signaling tracking filtering condition of the current signaling tracking task, the reported signaling message is resolved to obtain the signaling message of the signaling tracking task. The invention realizes a signaling tracking scheme in an ASON and can establish multiple signaling tracking tasks at the same time, as each signaling tracking task can set its own signaling tracking filtering condition; a flexible signaling tracking is achieved. The invention provides a means for resolving a signaling process and locating a fault in a field debugging and a subsequent operation and maintenance, thus improving the efficiency of fault location.