To improve mechanical properties of RDX based aluminized explosives, the RDX based aluminum fiber explosive was prepared by replacing aluminum powder in aluminized explosive with aluminum fiber. The fitting calculation of the elastic modulus and uniaxial compression strength of aluminum fiber explosive with different content of aluminum fiber obtained by quasi-static compression mechanical experiment was carried out. The relation expression of the elastic modulus and compression strength with aluminum fiber volume content for aluminum fiber explosive was obtained. Results show that the reinforcement coefficient of aluminum fiber obtained by fitting experimental data of elastic modulus is 8.19. The aluminum fiber can significantly enhance the mechanical properties of aluminum fiber explosive. With increasing the aluminum fiber content, its elastic modulus, compression strength and residual strength of aluminum fiber explosive increase When aluminum fiber volume content is 0%-30%, the critical strain of aluminum fiber explosive increases. When aluminum fiber volume content is higher than 30%, the critical strain of aluminum fiber explosive does not change The fitting of the engineering stress-strain curves of aluminum fiber explosive with aluminum fiber volume content of 10%-40% is performed by a normal distribution function, its fitting correction coefficient of determination is 0.987-0.998. The uniaxial compression strength of aluminum fiber explosive with specific aluminum fiber content of less than 38.1% for volume fraction can be calculated by the proposed relation.