Upper Darby High School Model UN is the high school’s very own MUN team. Established in 2024, the club has served as the connection between students' interest in international politics at UDHS and conferences within the Greater Philadelphia Area. The delegation from UDHS typically attends MUN conferences in the South Jersey area, with the most prominent conferences including, but not limited to, South Jersey Model United Nations (SJMUN) at Eastern Regional High School, Quaker Model United Nations Conference (QMUNC) at Moorestown Friends School, and Haddonfield Model United Nations (HadMUN) at Haddonfield Memorial High School, among others.

In April 2026, the UDHS Model UN team, under the leadership of Shahil Rihad and Mark Hodges, would host Upper Darby Model United Nations (UDMUN), the first-ever high school Model UN conference in Southeastern Pennsylvania. Various guest speakers, such as PA State Senator Tim Kearney, State Representative Gina H. Curry, and a keynote address from Mary Beth Tinker from the landmark Tinker v. Des Moines Supreme Court Case, helped set the tone for the event. Visiting delegates spent hours debating the complexities behind the right to free expression, especially during divisive times.