Charles II Otto (German: Karl II.
Otto) (5 September 1625 – 30 March 1671) was the Duke of Zweibrücken-Birkenfeld from 1669 until 1671.
Charles Otto was born in Birkenfeld in 1625 as the only son of George William, Count Palatine of Zweibrücken-Birkenfeld.
Charles Otto died in Birkenfeld in 1671 and was buried in Meisenheim.
Charles Otto married Margaret Hedwig of Hohenlohe-Neuenstein (1 January 1625 – 24 December 1676), daughter of Count Kraft VII, on 30 November 1616 and had the following children: