Peter Desnoyers (April 21, 1800 – March 6, 1880) was a businessman and politician from Detroit, Michigan, and served as an early State Treasurer of Michigan.

[1] The younger Peter Desnoyers lived in Detroit during his childhood, and began a career as a merchant in 1821.

The couple had two daughters: Frances Agnes and Catherine M.[1] Desnoyers was elected county treasurer of Wayne County, Michigan, in 1826, the first man to be elected to that position.

In 1827 he was elected alderman of the city of Detroit, and in 1831 he was appointed a United States Marshal by President Andrew Jackson, a position he held until 1837.

In 1838 he was appointed city treasurer of Detroit, and in 1839 Governor Stevens T. Mason appointed him State Treasurer of Michigan, a post which he served until Mason left office in 1840.