A steel sheet for cans which exhibits excellent weldability; and a production method therefor include a steel sheet for cans with the surface of a steel sheet in order from the steel sheet side, a chromium metal layer and a hydrous chromium oxide layer. The deposited amount of the chromium metal layer is 65-200 mg/m2. The deposited amount of the hydrous chromium oxide layer in terms of chromium is 3-30 mg/m2. The chromium metal layer includes: a base part having a thickness of 7.0 nm or higher; and granular protrusions which are on the base part, have a maximum grain size of 100 nm or lower, and have a number density per unit area of at least 200 per μm2.