arm of Lake Ontario (Ontario, Lake), southeastern Ontario, Canada, extending for 75 miles (121 km) from its entrance near Amherst Island to Murray Canal at the western end. It is a narrow bay, ranging from one to six miles in width. The bay is scenic, having many small inlets; and it receives several rivers from the north, including the Trent, Moira, Salmon, and Napanee. The head of the bay connects with Presqu'ile Bay and Lake Ontario through the Murray Canal; the Trent Canal runs northwestward to Georgian Bay. Major settlements around the bay include Trenton, Belleville, Deseronto, and Picton.

In 1615 the French explorers Étienne Brûlé (Brûlé, Étienne) and Samuel de Champlain (Champlain, Samuel de) became the first Europeans to enter the Bay of Quinte. From 1668 to 1680 French missionaries were based near Trenton. The bay's name was derived from Kenté, an Indian village that was situated at its west end. Tyendinaga Mohawk Territory lies along part of the northern shore.