Fatigue　damage　is　one　of　the　most　critical　sources　to　cause　the　failure　of　engineering　structures.　The　traditional　strain-based　sensors　used　in　the　bridge　health　monitoring　system　are　not　efficient　for　the　fatigue　accumulative　damage　monitoring,　because　these　sensors　normally　do　not　have　the　capacity　to　automatically　take　down　the　fatigue　accumulation　that　is　the　key　feature　in　the　fatigue　life　monitoring　of　bridges.　In　the　frame　of　developing　a　kind　of　bridge　fatigue　life　gauge　that　can　store　and　accumulate　the　changes　of　the　electric　resistance　automatically,　this　paper　presents　the　technique　of　preparing　the　resistance　alloy　foils　that　is　the　key　issue　in　the　development　of　such　a　fatigue　life　gauge.　Studies　include　the　optimisation　of　resistance　alloy　components,　selection　of　heat　treatment　parameters　of　sensitive　material,　techniques　of　gauge　capsulation　and　the　methods　to　test　the　resistance-life　performance　of　such　a　sensor.　The　developed　fatigue　life　gauge　has　a　great　theoretical　and　practical　significance　in　the　real-time　health　monitoring　system　of　bridges.