The invited guests included Vice President Joe Biden, former President Bill Clinton and Michelle Obama, wife of the current president, The (Gaithersburg) Gazette reported. Shriver's family opened the service at Our Lady of Mercy Catholic Church in Potomac to the public, although most ended up in an overflow room.
Cardinal Donald Wuerl, archbishop of Washington, celebrated the funeral mass at the church where Shriver and his wife worshiped for more than 20 years.
Shriver, who died Tuesday at 95 after years struggling with Alzheimer's disease, was one of the last surviving leaders of John F. Kennedy's administration. His wife, Eunice Kennedy Shriver, died in 2009.
Maria Shriver, wife of former California Gov. Arnold Schwarzenegger, told the congregation she is comforted by knowing "Daddy is in heaven with God and with Mummy," ABC News reported.
Shriver also founded the Job Corps and Head Start and ran for vice president with Sen. George McGovern in 1972.
Mary Ann Orlando, Shriver's onetime assistant, remembered the days of the Kennedy administration at a lunch Thursday, the 50th anniversary of Kennedy's inauguration.
"We had it down to a science," she told The New York Times. "We'd work Tuesday, Thursday and part of Saturday at the Peace Corps, and then we'd work Monday, Wednesday and Friday at the poverty program. And then we'd work Sunday to catch up."
Shriver will be buried next to his wife on Cape Cod.