AbstractBACKGROUNDThis work focuses on removing metal ions (Fe3+, Cu2+, and Zn2+) from aqueous solutions and real wastewater by underwater plasma.RESULTSResults show that the joint presence of Fe3+, Cu2+, and Zn2+ are needed for effective precipitation of these ions from aqueous solutions. The short‐time underwater plasma treatment leads to more effective removal of metal ions from real wastewater compared to treatment facilities of a factory.CONCLUSIONSRemoving metal ions from aqueous solutions of their mixture by underwater plasma occurs via formation of non‐dissolved substances on the base of metal oxide/hydroxide. Efficient removal of metal ions from real wastewater allows the creation of a prototype setup as one of the blocks of treatment facilities at a chemical factory. © 2019 Society of Chemical Industry