William Buel Franklin (February 27, 1823 – March 8, 1903) was a career Army officer and Union Army general in the American Civil War.

Franklin was born at York, Pennsylvania, graduated from the United States Military Academy first in his class in 1843, and joined the Topographical Engineers. He served under Philip Kearny during the Mexican-American War and received a brevet promotion to first lieutenant in the Battle of Buena Vista. In 1859 he replaced Montgomery C. Meigs as the engineer supervising construction of the United States Capitol Dome.

Soon after the beginning of the Civil War Franklin was appointed Brigadier General of Volunteers. He rose from brigade to corps command in the Army of the Potomac and saw action in the Peninsula Campaign, the Battle of Antietam, and the Battle of Fredericksburg. At Antietam, his VI Corps was in reserve and he tried in vain to convince Maj. Gen. Edwin V. Sumner to allow his corps to exploit a weakened position in the Confederate center. At Fredericksburg he commanded the “Left Grand Division” (two corps, under John F. Reynolds and William F. Smith) that failed in its assaults against the Confederate right, commanded by Lt. Gen. Thomas J. "Stonewall" Jackson. Army of the Potomac commander Ambrose E. Burnside blamed Franklin personally for this failure, although he appears to have executed his orders exactly. As political intrigue swept the Union Army after Fredericksburg and the infamous Mud March, Franklin was alleged to be a principal instigator of the "cabal" against Burnside's leadership. Burnside caused considerable political difficulty for Franklin in return, offering damaging testimony before the powerful [[U.S. Congress Joint Committee on the Conduct of the War ]] and keeping him from field duty for months.

Franklin was reassigned to corps command in the Department of the Gulf and participated in the ill-fated 1864 Red River Campaign . He was wounded in the leg in Mansfield, Louisiana. Returning from the field with his injury, he was captured by Confederate troops in a train near Washington, D.C., in July, 1864, but escaped the following day. The remainder of his army career was limited by disability from his wound and marred by his series of political and command misfortunes. He was unable serve in any more senior commands, even with the assistance of his West Point classmate and friend, Ulysses S. Grant.

Following the Civil War, General Franklin relocated to Connecticut and became the general manager of the Colt Firearms Manufacturing Company. He later served as the U.S. Commissioner-General for the Paris Exposition of 1888. He died in Hartford, Connecticut and is buried near his birthplace in York, Pennsylvania.