A highly sensitive micro-pressure sensor based on Fabry-Pérot interferometer (FPI) is proposed. A miniaturized, highly sensitive and accurate optical fiber micro-pressure sensor is developed by establishing a structural model of Fabry-Pérot (F-P) cavity end-face coating, and its response characteristics are experimentally studied. Experimental results show that the sensor has a sensitivity of -3 854.25 nm/MPa, a measurement range of 0.008 MPa, a linearity of 0.997, a free spectral range of 33.03 nm and an F-P cavity length of 36.32 nm. The proposed sensor is compact, simple and low cost, which has a high sensitivity and a good pressure response characteristic.