The ignition and extinction of n-butyl nitroxyethylnitramine (BuNENA)-plasticized polyethylene glycol (PEG) propellants were investigated with respect to the concentration of binder and the ratio of plasticizer to polymer (pl/po). A distinctive change in the ignition delay time (t(ign)) of the propellants was found at a low pressure of 0.03 MPa, where t(ign) increases as the binder concentration increases from 24 % to 32 % and decreases when the pl/po ratio reaches from 1 to 6. The kinetic analysis shows that the ignition delay of BuNENA-PEG propellants is due to a high activation energy of a condensed phase accompanied by the reduction of NO in the gas phase that plays an important role in the formation of luminous flames. Furthermore, the BuNENA-PEG propellants with a high concentration of binder or a low ratio of pl/po were found to result in a relatively high value of the pressure deflagration limit (PDL) under which steady combustion cannot occur. With regard to combustion stability, it seems that the BuNENA-PEG propellants producing relatively large amounts of CO and H-2 are easy to extinguish and exhibit significant delay in ignition at low pressure.