The 2011 Major League Soccer season was the 99th season of FIFA-sanctioned soccer, the 33rd with a national first-division league, in the United States and Canada, and the 16th season of Major League Soccer. The season marked the arrival of two new league clubs, Portland Timbers and Vancouver Whitecaps FC, whose cities previously had clubs of similar name play in the USSF D2 Pro League. Those two new West Coast clubs led to a realignment of the league's conferences, with Houston Dynamo moving to the Eastern Conference to create two conferences of nine teams each.
Each team played a balanced 34-match regular season schedule, playing every team twice (once at home and once away). The regular season began on March 15, when theLos Angeles Galaxy defeated the Seattle Sounders FC 1–0 at Qwest Field, and concluded with the host Houston Dynamo defeating the Los Angeles Galaxy 3–1 on October 23 at Robertson Stadium. The season also featured the 2011 MLS All-Star Game on July 27, when Manchester United defeated the MLS All-Stars 4–0 at Red_Bull Arena (hosted by the New York Red_Bulls). The 2011 MLS Cup Playoffs ran from October 26 until November 20, when the Los Angeles Galaxy claimed their third MLS championship by defeating Houston Dynamo 1–0 in MLS Cup 2011 at Home Depot Centerin Carson, CA.
The 2011 Los Angeles Galaxy season was the club's 17th year of existence as well as their 16th season in Major League Soccer and their 16th consecutive year in the top-flight of American soccer. The Galaxy entered the season as the defending MLS Supporters' Shield titleholders.
Most notably, the Galaxy became the third straight team to win consecutiveSupporters' Shields, after D.C. United (2006–07) and Columbus Crew (2008–09). The Galaxy clinched their fourth Shield on October 8, after Seattle Sounders FC lost 0–2 at home to Philadelphia Union. They also won their third MLS Cup, defeating Houston Dynamo 1–0 in the final.
Outside of league play, the Galaxy participated in the CONCACAF Champions League and the U.S. Open Cup, reaching the Quarterfinals in both competitions. Along with these competitive tournaments, the Galaxy played in the friendly-match World Football Challenge, losing to Real Madrid and drawing to Manchester City.
Their record in all competitions (yet excluding their Asia-Pacific tour) was 28–9–11, earning 95/144 points from 48 matches.