The Rotherham trolleybus system once served the town of Rotherham, West Riding of Yorkshire, England. Opened on 3 October 1912, it was the fourth trolleybus system to be established in the United Kingdom, after the systems in nearby Bradford and Leeds, which had opened simultaneously in 1911, and Dundee earlier in 1912. Between 1912 and 1949, the Rotherham system gradually replaced the Rotherham Tramway.
By the standards of the various now-defunct trolleybus systems in the United Kingdom, the Rotherham system was a medium-sized one, with a total of 10 routes, and a maximum fleet of 80 trolleybuses. It was closed on 2 October 1965.
Three of the former Rotherham trolleybuses are now preserved, two at the Trolleybus Museum at Sandtoft, and the other by the Rotherham Trolleybus Group at Burton upon Trent, Staffordshire.
Rotherham 37 is essentially suitable for passenger service, but a recent fitness test has suggested some remedial work is required before it re-enters service at the Museum.
37 is owned and maintained by the Rotherham 37 Trolleybus Group.
The vehicle can be seen at the Museum.