Paulo Ribenboim (born March 13, 1928) is a Brazilian-Canadian mathematician who specializes in number theory.

He received his BSc in mathematics from the University of São Paulo in 1948, and won a fellowship to study with Jean Dieudonné in France at the University of Nancy in the early 1950s, where he became a close friend of Alexander Grothendieck.

Andrew Granville, Jan Minac, Karl Dilcher and Aron Simis have been doctoral students of Ribenboim.

[3] The Ribenboim Prize of the Canadian Number Theory Association is named in his honor.

In 1951, Ribenboim married Huguette Demangelle, a French Catholic woman who he met in France.