The release of large quantities of heavy metals (e.g., Zn, Cu, Pb, Ni, Cd, etc.) into the natural environment has resulted in a significant number of environmental problems, disorderliness in human physiology, and other biological systems due to their high toxicity to plant, animal, and human life. This review paper explores the feasibility of diatomaceous earth for the adsorption of heavy metals from wastewater, its application in metal adsorption, and wastewater purification. Impregnating the diatomite surface with 0.38 g/g of manganese oxide gave a 2.4-fold increase in the adsorbent surface area. A number of equilibrium studies demonstrated that treated diatomite has a higher removal capacity for heavy metals from water than untreated diatomite. The future challenges and prospect of diatomite were also addressed. Conclusively, it was established that the use of diatomaceous earth is a promising technology in the removal of heavy metals from wastewaters and environment