The Louisville Southern Railroad (abbreviated: LS) was a 19th-century railway company in the U.S. state of Kentucky. It operated from 1884 until 1894, when it was incorporated into the Southern Railway in Kentucky.
Originally incorporated as the Louisville, Harrodsburg and Virginia Railroad in 1868, no track was laid until the early 1880s. When the Louisville, New Albany and Chicago Railway was chartered in 1882 and began an attempt to challenge the L&N's access to the Eastern Kentucky Coalfields, the LH&V was reörganized as the Louisville Southern and hired the LNA&C's president, Louisvillian Bennett Young. Construction commenced in 1884 and ran from Louisville through Shelbyville and Lawrenceburg to Harrodsburg, which was reached in 1888. A spur was constructed to Burgin, where the Louisville Southern joined the Cincinnati Southern's mainline.
In 1888, the Louisville Southern also began a spur from Lawrenceburg to Versailles and Lexington. It then purchased the Versailles and Midway and initiated service to Georgetown. The line to Lexington crossed the Kentucky River at Tyrone by means of the 1,625-foot (495 m) Young's High Bridge and initiated service in October 1889.