Elissa Aalto (22 November 1922, Kemi – 12 April 1994, Helsinki; born Elsa Kaisa Mäkiniemi) was a Finnish architect and author.
She graduated in architecture from the University of Helsinki in 1949, and the same year she joined the office of Alvar Aalto. They married in 1952. She was involved in all competition projects the office undertook, and after Alvar Aalto's death in 1976 she managed the office and completed the unfinished projects, such as the Essen Opera House. She was also involved in alteration projects and the restoration of Aalto buildings, including the Rovaniemi Town Hall. She donated Aalto's drawings to the Alvar Aalto Foundation to make the material available for researchers. Elissa Aalto died in 1994, and was buried in Hietaniemi cemetery, in Helsinki, with her husband.