In June 1952, after being discharged from the Marine Corps, Box returned to the Lions. Box was the leading receiver on the 1952 Lions team that won the NFL championship. On October 19, 1952, he led a comeback victory over the Los Angeles Rams, with touchdown catches covering 64 and 10 yards. He led the NFL with 15 receiving touchdowns, ranked second in the league with 90 points scored, and again ranked among the league leaders with 924 receiving yards (fourth), 22.0 yards per reception (fourth), and 924 yards from scrimmage (sixth). His yards per reception in 1952 are still the most ever in Lions team history while his 15 touchdowns remained a team record until 2011. In the 1952 NFL Championship Game, a 17–7 victory over the Cleveland Browns, Box was used mainly as a decoy but was credited with a key block on Doak Walker's 67-yard touchdown run. After the 1952 season, Box was selected by the AP as a first-team All Pro player and was selected to play in the 1953 Pro Bowl.