To provide a hydrometallurgical process for zinc without conducting roasting, which efficiently collects zinc though using a small facility.

This process comprises pulping a concentrate having particle sizes of 10-30 μm with sulfuric acid containing trivalent ferric ions with a concentration of 10-30 g/L, into a pulp with a concentration of 1-5%, and leaching zinc at 50-70°C with steps divided into two or more, when obtaining the concentrate through floatation treatment for a ground ore of zinc, and pulping the obtained concentrate with sulfuric acid without roasting it to leach zinc. The process increases a leaching rate of zinc, by adjusting a particle size of the concentrate, reducing the concentrations of the pulp and an oxidizing agent, and instead reacting them in the steps divided into two or more, because when a reaction product (S) formed in a leaching step covers the surface of a mineral (ZnS), a leaching rate extremely decreases.