An all-fiber photonic crystal fiber(PCF) Fabry-Perot(F-P) sensor fabricated by femtosecond laser was designed and proposed in the paper.Femtosecond pulse laser was used as the processing light source,and the PCF side is processed by line-by-line engraving method with the object lens of 100× magnification and the three-dimensional processing platform.A pair of lines with 80 μm deep and 800 μm spaced was written by optimizing the laser focusing position and writing power on the side of PCF,and an all optical fiber F-P structure was prepared whose cycle was 0.98 nm;In the experiment,the spectral characteristics of the sensor in the temperature range of 40~120 ℃ were tested and analyzed,whose data acquisition was recorded at intervals of 10 ℃.As the temperature increased,the wavelength drifted toward the long wave direction.The temperature sensitivity and fitting linearity of the testing point,which were 9.73 pm/℃ and 0.997,were got via linear fitting the sampling data.