The present invention protects a clock synchronization frequency offset estimation method suitable for a WIA-PA network, and belongs to the industrial wireless sensor network technology field. The method comprises the steps of A using a sub-node in the WIA-PA network to receive a beacon frame broadcasted by a time source device at each time synchronization cycle to obtain a sending time stamp and a reception time stamp, and then using the difference value of the two time stamps as a time adjustment amount to adjust the local time; repeating the above processes and after a plurality of synchronization cycles, using a statistics signal estimation method to estimate the frequency offset individually; B when the node needs to report the own time, compensating the node time by utilizing the estimated relative frequency offset. According to the present invention, the time synchronization precision is improved effectively, the free increase of a synchronization error in the time synchronization cycle is contained, the synchronization period is prolonged, and the network communication cost and node energy consumption are reduced.