The　Sagnac　loop　mirror　of　high　birefringence　fiber　is　developing　greater　more　than　other　fiber　because　it　has　the　advantages　of　high　precision,　wide　spectrum　and　simple　structure　in　applications.　In　this　paper,　general　theory　of　Sagnac　loop　mirror　of　high　birefringence　fiber　is　presented.　Since　Sagnac　loop　mirror　of　high　birefringence　fiber　is　more　sensitive　to　its　environmental　temperature,　an　intelligent　temperature　measurement　system　based　on　Sagnac　loop　mirror　of　high　birefringence　fiber　is　designed.　A　1550nm-laser　is　used　as　source　light　going　through　the　high　birefringence　fiber　Sagnac　loop　mirror.　The　amplitude　of　output　beam　is　converted　into　electrical　signals　with　Photo-Diode　(PD),　and　the　signal　is　collected　by　the　MCU(Microcontroller　Unit)　to　complete　the　analog-digital　conversion.　After　calibration,　the　temperature　is　calculated,　and　then　shown　on　LCD　displayer.　Various　parts　of　the　electronic　measurement　system　are　introduced　in　details,　containing　MCU　C8051F020　with　microcontroller,　its　internal　AD-convert,　calibration　program　and　measurement　program　of　temperature.　The　fiber　optic　temperature　measurement　system　is　compact,　solid　with　good　portability,　as　well　as　independent　real-time　analysis　of　data　processing　capability.　It＇s　provides　a　good　preliminary　basis　for　implementation　the　new　fiber-optic　temperature　measurement　system.　And　this　system　has　broad　application　prospects　of　a　good　practice.　The　arrangement　of　temperature　measurement　is　from　30　degrees　C　to　50　degrees　C　with　accuracy　+/-　0.2　degrees　C　in　recent　research　experiment.