Ojima Domain (小島藩 Ojima-han?), also known as Kojima Domain, was a Japanese domain of the Edo period. It was located in Suruga Province in modern-day what is now part of the ward of Shimizu in the city of Shizuoka, Shizuoka Prefecture.
In May 1689, Matsudaira Nobunari, the adopted son of the castellan of Sunpu Castle, and a wakadoshiyori in the Tokugawa Shogunate was elevated from his former hatamoto status of 4000 koku, to daimyō status of 10,000 koku, and assigned the territory of Ojima, to the east of Sunpu, to be his domain. He was also authorized to start his own branch of the Matsudaira clan, the Takiwaki Matsudaira clan (滝脇松平家?). However, due to the small size of his domain, he was not authorized to build a castle, but ruled from a fortified residence, or jin'ya located on the west bank of the Okitsu River.