The team announced Thursday that James, a tight end out of Penn State, has agreed to a four-year contract. Terms were not disclosed.
The 6-foot-7, 261-pound James caught 78 passes for 1,005 yards and 11 touchdowns during his career with the Nittany Lions. His touchdown total is a school record for tight ends.
James, who grew up in suburban Pittsburgh, is the fifth of the Steelers' eight draft picks to sign. Pittsburgh has yet to agree to terms with first-round pick Bud Dupree.