Second civil war, Second Civil War, or civil war II may refer to
Historical wars
- Second English Civil War (1648–1649)
- Second Central American Civil War (1838–1840)
- Second Congo War (1998–2002), also referred to as a civil war
- Second Liberian Civil War (1999–2003)
- Second Libyan Civil War (2014–2020)
- Second Sudanese Civil War (1983–2005)
- Republic of the Congo Civil War (1997–1999), also known as the Second Republic of the Congo Civil War
Fictional or hypothetical wars
- The Second Civil War, 1997 made-for-television film
- Civil War II, a Marvel Comics comic book crossover storyline
- A hypothetical second civil war in the United States akin to the American Civil War, which has been covered in speculative fiction