The invention discloses a GSM data network-based traffic dispersion method and a system thereof. The method comprises the following steps: street stations or transmitting base station districts are built at a crossing on the periphery of a monitoring road and set as mark districts; data users attached to a GPRS/EDGE network activate a routing update program when passing by the districts; by monitoring signaling of a Gb port of the GPRS/EDGE network, the time for routing update of all users in the marked districts is acquired; by the time difference of routing update of the users at the marked districts at the two ends of a road, the time for the users to pass the road section can be acquired; after abnormal time samples are eliminated, and by being compared with an experience threshold value, the jam situation of the road section at the current time can be acquired; and by using an existing short message platform, corresponding road condition information is sent to the users who are near the jammed sections to notify the users to make a detour, so as to achieve the aim of traffic dispersion.