Sir Rabbie Langanai Namaliu GCL KCMG PC (3 April 1947 – 31 March 2023) was a Papua New Guinean politician.

He was appointed foreign minister in 2002, as part of the National Alliance Party government of Michael Somare.

Namaliu subsequently lost his seat of Kokopo Open at the 2007 Election but had not ruled out a future return to politics.

As a former prime minister of Papua New Guinea, he was a member of the Privy Council of the United Kingdom from 1989, and was styled "The Right Honourable" with the postnominal letters 'P.C.'.

After his defeat in parliament in 1992 he left politics to be with Nakikus, who had incurable leukaemia and was in hospital in Brisbane, Australia.