Hamamatsu Domain

 was a Japanese domain of the Edo period, located in Tōtōmi Province. It was centered on what is now Hamamatsu Castle in what is now the city of Hamamatsu in Shizuoka Prefecture.
Hamamatsu was the residence of Tokugawa Ieyasu for much of his early career, and Hamamatsu Castle was nicknamed due to Ieyasu's promotion to shōgun. The domain was thus considered a prestigious posting, and was seen as a stepping stone in a "daimyō"s rise to higher levels with the administration of the Tokugawa shogunate, such "rōjū" or "wakadoshiyori."
The domain had a population of 3324 samurai in 776 households at the start of the Meiji period. The domain maintained its primary residence ("kamiyashiki") in Edo at Toranomon until the An'ei (1772–1781) period, and at Nihonbashi-Hamacho until the Meiji period 
Holdings at the end of the Edo period.
As with most domains in the han system, Hamamatsu Domain consisted of several discontinuous territories calculated to provide the assigned "kokudaka", based on periodic cadastral surveys and projected agricultural yields.