The Kilmarnock and Troon Railway was an early railway line in Ayrshire, Scotland. It was constructed to bring coal from pits around Kilmarnock to coastal shipping at Troon Harbour, and passengers were carried. In 1841, when more modern railways had developed throughout the West of Scotland, the line was converted from a plateway to a railway and realigned in places. The line became part of the Glasgow and South Western Railway system. Much of the original route is part of the present-day Kilmarnock to Barassie railway line, although the extremities of the original line have been lost.