Kitamatsuura Peninsula (北松浦半島? Kitamatsuura Hantō) is a peninsula located in northwest Kyūshū, projecting northwest from an imaginary line drawn between Imari in Saga Prefecture and Sasebo in Nagasaki Prefecture, Japan. The peninsula is bounded by the East China Sea on the west and southwest, and by the Sea of Japan on the north. Most of the peninsula is within the boundaries of the city of Hirado and Nagasaki Prefecture. The general area of and near the peninsula is commonly called the Hokushō Region (北松地方? Hokushō Chihō).
Kitamatsuura Peninsula has many bays, inlets, and other coastal features along its shores. Imari Bay is located on the north, the Hirado Strait is located to the west between Hirado Island and the peninsula, and Sasebo Bay is found on the southwest. The peninsula is mainly basalt which forms a gently-sloping tableland and pediment, though it features many small hills and uneven terrain as well. The borders of the tableland are very steep.
There is abundant evidence of ancient landslide activity throughout the peninsula. Much of the land is covered in rice fields, irrigated largely by abundant reservoirs.