Delaware Route 12 (DE 12) is a state highway in Kent County, Delaware, United States. It runs from Maryland Route 314 (MD 314) at the Maryland border in Whiteleysburg east to an interchange with DE 1 near Frederica. The route follows a mostly rural alignment, passing through the towns of Felton and Frederica. DE 12 intersects U.S. Route 13 (US 13) in Felton and DE 15 east of Felton. What would become DE 12 was built as a state highway during the 1920s. DE 12 was designated between Felton and Frederica by 1936 and extended west to the Maryland border by 1938. The eastern terminus was moved to its current location in 1965 when US 113 was routed to bypass Frederica to the east. The DE 1 intersection became an interchange in 2011.

Kent County is a county located in the central part of the U.S. state of Delaware. As of the 2020 census, the population was 181,851, making it the least populous county in Delaware. The county seat is Dover, the state capital of Delaware. It is named for Kent, an English county.