The Cathedral Church of St. Barnabas is a cathedral of the Roman Catholic Church in the city of Nottingham in Nottinghamshire, England.

It was built between 1841 and 1844 by Augustus Pugin. Upon completion, the cathedral was the largest Catholic church built in England since the Reformation. It was built in the Gothic style, although in contrast, the Blessed Sacrament Chapel was richly decorated and Pugin's later churches were built in that Decorated Gothic style throughout.