Sir Khalifa II bin Harub Al-Busaidi GCB GCMG GBE (26 August 1879 – 9 October 1960) (Arabic: السيد خليفة بن حارب البوسعيدي) was the ninth Sultan of Zanzibar from 9 December 1911 to 9 October 1960.

His father was Harub bin Thuwaini, a son of Thuwaini bin Said, Sultan of Muscat and Oman. In 1900, he married Sayyida Matuka bint Hamud Al-Busaid, daughter of the seventh Sultan of Zanzibar and sister of the eighth Sultan. He also married his second wife, Sultana Nunu. He was succeeded by his eldest surviving son, Sayyid Sir Abdullah bin Khalifa.^{[citation needed]}

Part of the museum of the Sultan's Palace in Zanzibar is dedicated to Sir Khalifa.

• King George V Coronation Medal-1911
• Grand Cordon of the Saidi Order of Oman
• King George V Silver Jubilee Medal-1935
• Knight Grand Cross of the Order of the British Empire (GBE)-1935 (KBE-1919) (Honorary)
• Knight Grand Cross of the Order of St Michael and St George (GCMG)-1936 (KCMG-1914)
• King George VI Coronation Medal-1937
• Commander of the Order of the Shield and Spears of Buganda
• Queen Elizabeth II Coronation Medal-1953
• Knight Grand Cross of the Order of the Bath (GCB)-1956^{[citation needed]}