Riba was born in Ohio and received his professional training at the Pennsylvania Academy of the Fine Arts, PA, and graduated with highest honors from the Cleveland Institute of Art where he taught for fourteen years.

He was a member of Artist Guild of Palm Beach Art Institute. He worked as mural painter, advertising illustrator and instructor. Riba did many exhibitions including the Cleveland Museum of Art (permanently represented); National Academy of Design; Carnegie Institute; Illinois State Museum (permanently represented); Ohio State Capitol (permanently represented); Smithsonian Institute, Washington, DC; White House, Washington, DC; Cincinnati Art Galleries, Cincinnati, Ohio did a retrospective of his work in 2000. He also won many awards and honors including a Fellow of The Royal Society of Art in London.

Paul Riba was a painter of Magic Realism. He explored the unreal juxtaposition of objects with his own touch of exacting realism. He spoke of his work as "invitations to pause and enjoy."