A steel sheet for cans has, on the surface thereof, in order from the steel sheet side, a chromium metal layer and a hydrous chromium oxide layer. The chromium metal layer is deposited in an amount of 50-200 mg/m2, and the hydrous chromium oxide layer is deposited in an amount of 3-15 mg/m2 in terms of chromium. The chromium metal layer includes: a flat chromium metal layer that has a thickness of at least 7 nm; and a granular chromium metal layer that includes granular protrusions that are formed on the surface of the flat chromium metal layer. The maximum grain size of the granular protrusions is 150 nm or smaller. The number density of the granular protrusions per unit area is 10/μm2 or higher.