Sultan Abu Bakar Ri’ayatuddin Al-Mu’azzam Shah Ibni Al-Marhum Sultan Abdullah Al-Mu’tassim Billah Shah GCMG (Jawi: سلطان أبو بكر رعاية الدين المعظم شاه ابن المرحوم سلطان عبد الله المعتصم بالله شاه; 29 May 1904 – 5 May 1974), was the fourth modern Sultan of Pahang.

Born on 29 May 1904 at Istana Hinggap, Pekan, he was the second son of Sultan Abdullah Al-Mu’tassim Billah Shah by his second wife, Som binti Tun.

During the Japanese occupation of Malaya, he discreetly encouraged resistance movements such as the Askar Wataniah, Force 136 and the Malayan Peoples' Anti-Japanese Army.

[2] However, due to his penchant for marrying commoners, including several popular actresses and singers, he was less popular with other Malay rulers and they declined to choose him as Yang di-Pertuan Agong of Malaysia on five separate occasions.

[3] He died on 5 May 1974 at the Istana Peninjau, Kampung Padang Polo, Pekan at age 69 and was succeeded by his son Sultan Ahmad Shah.