Harald Kaas (19 May 1868 – 5 December 1953) was a Norwegian architect.
Born in Oslo, he studied at the Norwegian National Academy of Craft and Art Industry, then at Baugewerkschule in Eckernförde and finally at Polytechnicum in Munich. He was employed by the Norwegian State Railways from 1908 to 1914, and designed stations on the Arendal, Bergen and Solør Line for the company. Kaas died on 5 December 1953 and was buried on 20 May 1954.