The Mystic River Bascule Bridge is a bascule bridge, a type of drawbridge with counterweights, that spans the Mystic River in Mystic, Connecticut in the United States.

The bridge was built in 1922. It has a moveable span width of 85 ft (26 m) and a total length of 218 ft (66 m). It has a moveable span weight of 660 tons, with two concrete-filled counterweights, each of 230 tons. It is operated by the Connecticut Department of Transportation. connects the two halves of the town of Mystic, allowing vehicle and foot traffic on Main Street (33 ft wide) in the center of the tourist district of town.

It opens approximately 2200 times per year, with each opening lasting approximately 5 minutes. The opening of the bridge is driven by two 40 horsepower (30 kW) direct current motors, each weighing 1400 pounds (635 kg). The bridge is greased and inspected every 100 openings or every two weeks during the winter. From May 1 to October 31 the bridge opens at hourly intervals during daylight hours. Outside of this time it opens on demand.