The 150-seat theatre will make its home at 66 E. 4th Street, the same location as La MaMa's Ellen Stewart Theater.
The Downstairs, which will open to the public beginning Sept. 28, will also feature a classroom and an exhibition space. Part of the company's $30 million renovation and restoration project, the first tenant will be Shank's Mare, a Japanese-style puppet production that begins Nov. 6.
In a statement artistic director Mia Yoo said, "We are embracing 21st-century tools for collaboration and production."
Over 60 productions are scheduled for the 54-year-old company's 2015-16 season. For more information visit LaMaMa.org.