Casa Pia Atlético Clube, commonly known as Casa Pia, is a Portuguese multi-sports club founded in 1920 and based in Lisbon, Portugal, best known for its professional football team, that competes in the Primeira Liga. The club is named after Casa Pia, a Portuguese children's charity, and many of its athletes come from that institution. Its football stadium is Estádio Pina Manique, named in honor of Pina Manique, the founder of Casa Pia children's charity. Casa Pia AC was one of the most versatile Portuguese clubs, having played 25 sports, with the curiosity of having been the only one who practiced Baseball regularly, beating the strong team of the American Colony on 4 July 1923 at Campo das Laranjeiras by 25–24.

On 18 December 1921, when Portugal made their international debut against Spain in Madrid, Casa Pia FC provided the squad with four players in a 1–3 loss, including Cândido de Oliveira, who was the team captain. Casa Pia promoted from Serie E of Terceira Divisão to Centre Group of Portuguese Second Division in 2009–10 season as champions. They were promoted again to LigaPro in 2019. After a hiatus of 83 years, the team were promoted to the Primeira Liga in the 2022–23 season.