The invention discloses a method for entity authentication based on secret sharing encryption, which is suitable for a self-organizing network and relates to the field of safety-related application of a wireless network in an information safety technique. Aiming at the characteristics of limited energy consumption and storage of self-organizing network nodes, the scheme uses a secret sharing technique and a symmetric key algorithm to effectively reduce the authentication time delay and improve the network life time; and simultaneously, a plurality of times of authentications ensure that the safety is not reduced. Besides, when a cluster head is arranged in the self-organizing network, the invention also provides a power consumption minimization algorithm to shorten the distance of transmitted signals between nodes, effectively reduce the node energy consumption and improve the network life time.