William Carr Lane (December 1, 1789 – January 6, 1863) was a medical doctor and the first mayor of St. Louis, Missouri, serving from 1823 to 1829 and 1837 to 1840.

Born in Fayette County, Pennsylvania, to Presley Carr Lane and Sarah Stephenson, Lane attended college in Pennsylvania and studied medicine in Louisville, Kentucky.

He entered the U.S. Army, and was appointed post surgeon at Fort Harrison on the Wabash River north of Terre Haute, Indiana, in 1816.

During his tenure, Lane seized disputed land in the Mesilla Valley that he had no authority over.

He sought to use the land as a route for the transcontinental railroad, but President Franklin Pierce did not approve of the seizure.