The Middletown High School South Eagles compete in Division A North of the
Shore Conference, an athletic conference comprised of public and private high schools in Monmouth County and
Ocean County along the
Jersey Shore. The conference operates under the jurisdiction of the
New Jersey State Interscholastic Athletic Association (NJSIAA). With 1,096 students in grades 10–12, the school was classified by the NJSIAA for the 2019–20 school year as Group IV for most athletic competition purposes, which included schools with an enrollment of 1,060 to 5,049 students in that grade range. The school was classified by the NJSIAA as Group IV South for football for 2024–2026, which included schools with 890 to 1,298 students. In 2015, to commemorate the 100-year anniversary of football in Middletown, alumni of North and South high schools played each other; The Middletown North Lion football alumni defeated the Middletown South alumni 6–3 at The Swamp, to claim the victory in what was the first-ever game of its kind in Middletown. Each year, students, parents, teachers, alumni, and administrators gather for the annual Thanksgiving Day football game between Middletown North and Middletown South. The football team won the Central Jersey Group IV state sectional title in 1989, 1990, 1992 and 1995; won in Central Jersey Group III in 2001, 2003, 2004 and 2006; and won in 2015 in North II Group IV. Middletown South's football program holds ten state sectional championships, 17 Shore Conference Division Championships, 9 undefeated seasons and 29 state playoff berths. The football program holds the Shore Conference record for longest winning streak with 43 straight wins from 2003 to 2006, which was broken with a 19–14 loss in October 2006 to
Ocean Township High School. The 1989 team finished the season with an 11–0 record and was ranked 13th in the nation by
USA Today after defeating
Madison Central High School by a score of 22–3 to win the program's first Central Jersey Group IV title. The 1990 team won the North II Group IV sectional title with a 15–14 win against
Trenton Central High School in the championship game. In the 1995 Central Jersey Group IV final at
Giants Stadium, the team defeated
Piscataway High School by a score of 28–10 to finish the season with an 11–0 record. The 2001 team finished the season with a record of 12-0 after winning the Central Jersey Group IV sectional title with a 15–14 win against
Hamilton High School West in the tournament final. In 2004, The Eagles were ranked #1 in the state of New Jersey unanimously by Gannett New Jersey,
The Star-Ledger, and
News 12 New Jersey polls. The team was selected again in 2005 and in 2015 as the winner of the
Star-Ledger Trophy, recognizing the best team in the state. Middletown South's head coach is Steve Antonucci who had a career record of 149-34 as of November 2013. Middletown South was the high school of
Knowshon Moreno, who was the 12th pick of the
2009 NFL draft.
NJ.com listed the rivalry between Middletown North and South as 11th best in their 2017 list "Ranking the 31 fiercest rivalries in N.J. HS football". Middletown South holds the overall lead with a head-to-head record of 37–13–1 through the 2025 season. The Middletown South baseball program has also been recognized for their success in the 1990s. During Head Coach Steve Antonucci's tenure which started in 1996, the Eagles won two Central Jersey State Titles (1996 and 1999) and completed the first undefeated season in Shore Conference A-North history with a 14–0 record. The Eagles were led by
Darren Fenster to a 25–3 record. The baseball team won the Group IV state championship in 1996 (defeating
Bloomfield High School in the tournament final) and 2021 (vs.
Montclair High School). In 1999, the Eagles won the A-North, Monmouth County and Central Jersey state championships. The 1999 squad featured many talented players including
Asbury Park Press Player of the Year Jarrett Sues, who set a school record with 21 home runs and earned ten victories on the hill. The Eagles offense was the most potent in the state including the single season home run record as a team. The Eagles were also led by All-State pitcher John Scala (10-1), and All-Shore selections Jon Klopacs (C) and Mark Fitzgerald (SS). Antonucci would continue to lead the Eagles until the conclusion of the 2008 season. The 2011 baseball team won the Monmouth County Tournament and the Central Jersey, Group III title, the program's first since 1999. In 2012, the Eagles clinched the A-North division title. The softball team won the Group IV state championship in 1995 (vs.
Clifton High School), won in Group III in 2002 (vs.
Pascack Valley High School), 2009 (vs.
Ramapo High School), 2010 (vs.
Nutley High School) and 2015 (vs.
Sparta High School); the program's five state titles are tied for eighth-most in the state. The program's first title came in 1995 with a 9–4 win against Clifton in the championship game. The team won the Group III state championship in 2015, defeating Sparta High School by a score of 8–1 at
Kean University, to win the program's fifth overall group championship. Softball coach Tom Erbig retired at the end of the 2016 season having led the team to 16 sectional championships and five group titles; his career record of 743-231-1 made him the winningest softball coach in the state, a title he earned in 2015 with his 722nd win, surpassing Pete Fick of
Hunterdon Central Regional High School. The girls tennis team won the Group IV state championship in 1996, defeating
Westfield High School in the tournament final. The 1996 team defeated
Cherry Hill High School East 3–2 in the semifinal round before defeating Westfield 3–2 in the finals. The girls' track team won the Group III state indoor relay championships in 1997 and 1998. The girls track team was indoor Group II champion in 1997 and 1999. The girls track team won the spring / outdoor track Group III state title in 1998. The boys cross country team won the Group III state championship in 1998. The girls' cross country team won the Group III in 1998, 2002 and 2019. The team won the Meet of Champions in 1998. They won state sectionals for three consecutive years, 2011, 2012 and 2013. The girls' soccer team was Group III co-champion with
Cranford High School in 2000. The boys' basketball team did not win a single game in the 2004–05 season. Three years later, during the 2007–08 season, second-year head coach Kevin Cullen led the team to the Central Jersey Group III Sectional Championship with a win over
Neptune High School 45–33. The ice hockey team won Handchen Cup in 2009, 2010 and 2012 (as co-champion). The girls' basketball team won the Group III state championship in 2015, defeating
Northern Valley Regional High School at Old Tappan in the final game of the tournament playoff. The team won the Group III Central Jersey state championship in 2014 with a 38–35 win against
Neptune High School in the tournament final. The boys' golf team won three consecutive Public A North titles from 2021 to 2023. ==Administration==