As the waste residue generated in the process of aluminum recycling, the secondary aluminum ash has obvious chemical reactivity, leaching toxicity of toxic and harmful substances and other dangerous characteristics. In order to solve the problem of stockpiling and disposal of secondary aluminum ash generated in aluminum industry, the secondary aluminum ash was used as raw material to prepare high strength ceramsite through water washing, disk granulation and 1 200~1 400 ℃ heat treatment. The phase composition and micromorphologies of the ceramsite samples sintered at different temperatures were analyzed by X-ray diffractometer and scanning electron microscopy. The bulk density, apparent density, porosity and cylinder compressive strength of the ceramsite were tested. The results show that with the increase of heat treatment temperature, the internal structure of ceramsite becomes denser gradually, and the bulk density, apparent density and cylinder compressive strength increase. The main phases of ceramsite after heat treatment at 1 400 ℃ are corundum and magnesia alumina spinel. The apparent density, volume density and cylinder compressive strength of ceramsite are 182 g/cm3, 1.81 g/cm3 and 25.7 MPa, respectively, meeting the requirements of high strength ceramsite.