The ignition and combustion characteristics of NEPE propellant were studied based on a CO₂ laser ignition test platform established， in which the combustion processes of NEPE propellant in different gas environments were photographed using a high-speed camera and the ignition delay times of NEPE propellant were measured under the pressure of 0.1-3.0 MPa in nitrogen and air through a signal acquisition system. The results show that the ambient pressure and gas environment strongly affect the ignition and combustion process of NEPE propellant. The combustion of NEPE propellant becomes more intense as the increase of ambient pressure， and the burning of NEPE propellant appears more violent in air as compared to that in nitrogen. The ignition delay time of NEPE propellant decreases with the ambient pressure increases in the range of 0.1 MPa to 3.0 MPa. Specifically， the reduction in ignition delay time of NEPE propellant is observed from 0.51 s to 0.29 s in nitrogen and from 0.32 s to 0.18 s in air. However， when the ambient pressure exceeds 0.5 MPa， the influence of the ambient pressure on the ignition delay time becomes insignificant. In addition， the burning rate of NEPE propellant is also found to be effectively affected by the ambient pressure. With the ambient pressure increases from 0.1 MPa to 3.0 MPa， the enhancement in burning rate of NEPE propellant can be seen from 1.71 mm·s^-1 to 4.54 mm·s^-1 in nitrogen and from 2.51 mm·s^-1 to 11.4 mm·s^-1 in air， and thus a stronger increase in the burning rate is observed in air. Finally， the experimental data of burning rate were fitted by an empirical formula， which indicates the Vielle burning rate formula is more suitable for reproducing the burning rate characteristics of NEPE propellant especially at 0.1-3.0 MPa.