The preparation of hydroxylammonium nitrate (HAN) hydrogel was introduced and related properties of the gel was characterized. Based on the closed bomb test,the combustion characteristics of the gel with different water contained were studied. The energy of the gel with the water content 34.92% can reach 757.58 J·g^-1,and the burn time less than 52.30 ms. The hydrogel can be applied to solid propellant system and the safety brake system.