The invention discloses an event sequence fault positioning method. The positioning method is applied to a testing system. The method comprises the following steps: triggering a plurality of testing event sequence excitations one by one to obtain a triggering result; acquiring a correct excitation set and a fault excitation set according to the triggering result; calculating a system safety value set according to the correct excitation set; generating an additional testing event sequence according to the safety value set and the fault testing excitations; carrying out fault event sequence positioning to obtain a fault event sequence. Fault event sequence positioning analysis is carried out by the aid of the safety value set and the fault testing excitations, and the fault event sequence is positioned rapidly and accurately.