Abstract: Multi-step target is important to measurement of equation of state (EOS) under high pressure and is the important target used in measurement of stability and planarity of shockwave. The pure aluminum two-sided multi-step target used in EOS experiment was manufactured with rational technical process design by diamond turning technology. The surface quality was characterized by means of Veeco NT1100 device. The results indicate that surface root mean square roughness of aluminum steps target is less than 50 nm and the primary maximum peak to valley height is less than 200 nm. Verticality of step is 90°±1° by optical microscope.