Frobisher Bay is an arm of the Atlantic Ocean. It is 240 km (150 miles) long and between 32 and 64 km (20 to 40 miles) wide. The bay cuts deep into the southeastern part of Baffin Island. It has steep, deeply indented shores and there are numerous islets. On the southwestern side of the bay are the Grinnell and Southeast icecaps, which rise some 900 m (3000 feet) above sea level and boast extending tongues into the bay.

At the head of Frobisher Bay is Iqaluit, the capital of Nunavut. The bay was first explored by English mariner Sir Martin Frobisher and named after him. Until 1860, it was believed to be a strait separating Baffin from another island.