Foxboro Stadium was an outdoor sports venue located in Foxborough or Foxboro, Massachusetts. It was built in 1971 as the home venue for the New England Patriots of the National Football League. The Patriots were previously the Boston Patriots of the American Football League, which entered into an agreement to merge with the NFL in 1966 effective with the 1970 season. The Patriots had played their home games from 1963 to 1968 in Fenway Park, home of baseball's Boston Red Sox, which was poorly suited to be a football venue and also had an inadequate seating capacity.

Foxboro Stadium was built at announced cost of $4,000,000, a very small amount, even at the time, for a major sports stadium. Because of this, and also the era in which it was designed and built, it had very few amenities of the type that became commonplace at football stadiums a short time later, such as chairback seating, "club seats", luxury suites, and deluxe locker rooms for the teams. As premium seating became a major source of revenue for professional sports teams, Foxboro Stadium became functionally obsolete.

Like the majority of outdoor sports venues built in the U.S. at the time, Foxboro Stadium was designed for the use of an artificial turf playing surface. When this practice fell out of favor in the 1990's due to the supposed higher level of injuries resulting from play on the artificial surface, the field's surface was replaced by natural grass, as it was at many other facilities. At Foxboro Stadium the replacement grass field never seemed to drain properly, resulting in the playing surface often becoming a quagmire during wet playing conditions.

Foxboro Stadium also served as the venue at times for the home football games of Boston College, and hosted numerous other outdoor events, primarily concerts. When built it was initially referred to as Schaefer Stadium for the brewery of that name in an early example of the sale of naming rights. When this agreement expired no new sponsor stepped forward, perhaps in part because that by this point the facility was already regarded as being substandard, and it became known as Sullivan Stadium in honor of the family who was at the time the majority owners of the Patriots. Only after the Sullivan family sold their majority interest in the team did it actually become known officially as Foxboro Stadium.

Foxboro Stadium was demolished after the conclusion of the 2001 season (the season in which the Patriots won their first Super Bowl). Its former site is now one of the parking lots of its successor, Gillette Stadium.