Abstract: An immunization detection method for a user behavior mode in an electronic transaction process, comprising a data preprocessing step of mainly processing a user operation process into a sequence format and cleaning related repeated data; a training step of mainly calculating an age value of each sequence according to a time order and according to an age evolution process, deleting aged logs according to the age values and extracting a normal sequence library; a detection step of mainly detecting whether a newly generated transaction sequence is mutated or not; and an updating step of updating age values of selves and non-selves in time according to a detection result and updating a related library set. The method is oriented to abnormal situations in the electronic transaction process, which may be misoperation by users.