A method and apparatus for accessing a wireless sensor network are provided in embodiments of this invention. The technical solution provided in embodiments of this invention includes: when receiving a first beacon frame, stopping channel scan temporarily, and establishing a new channel scan sequence according to operating channels of a current wireless sensor network recorded in the beacon frame. Non-operating channels are not included in the new channel scan sequence. Time for performing subsequence channel scan is reduced, so that the process of accessing the current wireless sensor network of a device node expecting for network can be accelerated.