A high sensitivity fiber grating pressure sensor using the enhance-sensitivity-coated jar has been designed and studied. The pressure sensitivity is up to -5.277 nm/Mpa, which is corresponding to the sensitivity coefficients of -3.41×10 -3 Mpa -1. The sensitivity is about 1722 times the value of the bare fiber. The linearity is very good. This kind of sensor has potential applications in the sensing measurement at low-pressure.