The 1978 Pittsburgh Steelers season was the franchise's 46th season in the National Football League (NFL). The season concluded with the team winning Super Bowl XIII to become the first franchise in the NFL to win three Super Bowl titles. The championship run was led by quarterback Terry Bradshaw and the team's vaunted Steel Curtain defense. Bradshaw put together the best year of his career to that point, becoming only the second Steeler to win the NFL MVP award. Ten Steelers players were named to the Pro Bowl team, and four were judged as first-team All-Pros by the AP. Head coach Chuck Noll returned for his tenth season—moving him ahead of Walt Kiesling as the longest tenured head coach in the team's history to that point.
The Steelers entered the season as defending champions of the AFC Central Division, coming off a 9–5 record in 1977. Despite winning their division, the previous season was a difficult one for the team (both on and off the field) which culminated in a division round playoff loss to the Denver Broncos on Christmas Eve.
The team began the 1978 season with seven straight victories, before losing to the Houston Oilers in prime time on Monday Night Football. They finished the season with a league-best 14–2 record, including a 5-game winning streak to close the season. This record assured them they would play at home throughout the 1978 playoffs. It was also the best record compiled in the team's history (since surpassed only by a 15–1 mark in 2004).