In order to meet the requirement of monitoring temperature change during the NaCl solution concentration measurement, an interferometric sensor based on Mach-Zehnder interferometer(MZI) cascaded Fabry-Perot interferometer(FPI) was proposed. The MZI was prepared by melting and splicing a single mode fiber to form a pair of tapers structure with diameter of 155 ?滋m at the waist an interval of 1.5 cm and the contrast and period of the MZI was 10 dB and 29.85 nm, respectively; Then a photonic crystal fiber (PCF) was spliced to one end of the MZI, cleaving the PCF at a distance of a 176 ?滋m from the splicing position, which a FPI was formed with contrast and period of 8 dB and 5.71 nm, respectively. By selecting the characteristic wavelength shifts of MZI and FPI interference dips in the range of 1 535-1 555 nm, in the temperature range of 30-150 ℃ and NaCl solution concentration range of 0%-24%, the temperature and refractive index sensitivities were 50 pm/℃ and 9.97 nm/RIU, respectively. The linearities were both greater than 0.97; While the interference dip of FPI was insensitive to the refractive index, and its sensitivity of temperature and linearity was 8.3 pm/℃ and 0.98, respectively. Finally, the sensitivity matrix for temperature and NaCl concentration was calculated by constructing the temperature-NaCl concentration function matrix. The interferometric sensor has good sensitivity and linearity to temperature and concentration of NaCl solution, which can realize the simultaneous measurement of the mentioned parameters.