The Adriatic Mills were a historic industrial complex on Armory Street in Worcester, Massachusetts. In 1854 Eli Thayer (best known for his abolitionist activities) constructed a stone industrial building known as the Lower Junction Shop, which was 400 feet (120 m) long and 40 feet (12 m) wide. He apparently rented the space to manufacturing interests, before selling it in 1859 to Benjamin F. Joslyn, an arms manufacturer. He manufactured the Joslyn rifle, the first breech-loading rifle, on these premises before selling them in 1863 to the Jordan Marsh Company. Jordan Marsh expanded and repurposed the premises for the production of textiles, and gave the complex the name "Adriatic Mills". It continued to be used for textile production into the 1920s.
The complex was listed on the National Register of Historic Places in 1980, at which time it was being used as a foundry by the Chromalloy Corporation. It has since been demolished (c. 2009) to make way for redevelopment.