A new powdery ammonium nitrate fuel oil explosive was produced to solve the problems of complicated production process and low explosion energy. The explosive was made of ozocerite,surfactant,gelatinizer and water, which were made into slurry mixed solution at 105-110 ℃, and was dehydrated from -0.07 MPa to -0.09 MPa. The microstructure and sensitivity of the explosive were analyzed,and the effects of the charge density on detonation velocity and underwater explosion energy were also studied. Results show that the mixing uniformity of the components and safety are good. When the charge density is 0.91-0.94 g·cm^-3,the detonation velocity is more than 4000 m·s^-1, and the underwater explosion energy is more than 3700 kJ·kg^-1,which is close to the theoretical calculation value.