Alexandru Ioan Lupaș (5 January 1942 – 14 August 2007) was a Romanian mathematician.
He was born in Arad, where he attended the Moise Nicoară High School. He pursued his studies at Babeș-Bolyai University in Cluj, obtaining a B.S. degree in Mathematics in 1964. He earned a Ph.D. degree in 1972 from the University of Stuttgart, under the direction of and Friedrich Moritz Lösch.
Lupaș then returned to work at Babeș-Bolyai University, obtaining a second Ph.D. degree in 1976 under the supervision of Tiberiu Popoviciu and . That year he moved to Lucian Blaga University of Sibiu, starting as lecturer and advancing to full professor in 1990. He died in Sibiu.