Stephen Gardner Champlin (July 1, 1827 – January 24, 1864) was an American physician, lawyer, soldier, and judge.

He served in the Union Army during the American Civil War, rising to the rank of brigadier general before succumbing to wounds he received in combat.

He received his initial education at local public schools, and then he attended the academy at Rhinebeck in Dutchess County for a single term.

He attended State and National Law School for two terms, and in 1850 he continued his studies with Theodoric R. Westbrook in Kingston.

[4] Champlin was commended for his actions during the battle by divisional commander Maj. Gen. Philip Kearny, shortly before the latter's own death in combat.

While resting in Washington, D.C., he wrote to Michigan Governor Austin Blair on January 3, 1863, formally resigning his command of the 3rd due to his promotion.

His funeral was conducted at St. Mark's Church in Grand Rapids on January 28, and he was buried there in Fulton Street Cemetery.