Layered double hydroxides (LDHs) are anionic clay with a special layered structure, which are of great interest for wastewater treatment because of their adjustable chemical composition, large specific surface area and unique structural memory effect. Tuning the structure of LDHs is an effective way to further expand its application and improve its adsorption performance. The special layered structure of LDHs and their own properties are firstly introduced. Secondly, the five most commonly used preparation methods of LDHs, namely co-precipitation, ion exchange, urea hydrolysis, calcination recovery and sol-gel method, are mainly summarized, and the principles and characteristics of each preparation method are introduced respectively. Then the influence of structural tuning of LDHs on their adsorption performance for heavy metal ions are reviewed, and the adsorption mechanism of LDHs on heavy metal ions is summarized. Finally, the challenges faced by the current research on LDHs in the treatment of wastewater containing heavy metal ions are pointed out, and the future research directions and development trends of the materials are prospected.