Peter Sinclair (November 13, 1819 – October 9, 1906) was a Scottish farmer and politician in Prince Edward Island. He represented Queen's County in the Canadian House of Commons from 1873 to 1878 as a Liberal member.He was born in Glendaruel, Argyleshire, the son of Peter Sinclair, and came to Queens County, Prince Edward Island in 1840 with his mother. He was an unsuccessful candidate for a seat in the provincial assembly in 1858.