Between 1931 and 1934, the station underwent a major rebuild, designed by the GWR's architects department under their chief architect Percy Emerson Culverhouse, the centrepiece of this was a new Art Deco entrance building faced in Portland stone, containing a booking hall and concourse with noted Art Deco light fittings, all topped by a clock cupola.
The current Art Deco lamps in the booking hall are replicas of the originals, installed in 1999, having been funded by the Railway Heritage Trust.
A GWR war memorial is located at the eastern end of the concourse.
The Great Western Railway has its full name carved onto the façade (larger than the name of the station).
The rebuild also saw a number of other improvements including the lengthening of the platforms, the widening of the Taff River railway bridge to allow the approach lines to the station to be quadrupled, and the installation of colour-light signalling.
The rebuild of the station cost the GWR £820,000 (equivalent to £58,640,000 in 2019),, and was formally opened by the then Minister of Transport Oliver Stanley on 26 February 1934.

In July 1934, the GWR began a pioneering diesel railcar service with a buffet between Cardiff General and Birmingham Snow Hill which had only two stops at Newport and Gloucester.
This was the first long distance diesel express service in Britain, covering the 117.5 miles (189.1 km) between Cardiff and Birmingham in 2 hours 20 minutes.
It proved so successful that larger railcars with more seating and no buffet had to be introduced to cope with demand, and even this had to be augmented by a normal locomotive hauled service.
During the Second World War, two such trains ran to and from Cardiff daily.
At this time it consisted of a three car train consisting of a standard carriage sandwiched between two railcars, and a stop at Stratford-upon-Avon was introduced.

As a result of representations by the GWR, a nearby working-class district, Temperance Town, was cleared during the late 1930s in order to improve the outlook of the rebuilt station.

In 1992, the station, its entrances and platforms, became Grade II listed.
Between 1931 and 1934, the station underwent a major rebuild, designed by the GWR's architects department under their chief architect Percy Emerson Culverhouse, the centrepiece of this was a new Art Deco entrance building faced in Portland stone, containing a booking hall and concourse with noted Art Deco light fittings, all topped by a clock cupola. The current Art Deco lamps in the booking hall are replicas of the originals, installed in 1999, having been funded by the Railway Heritage Trust. A GWR war memorial is located at the eastern end of the concourse. The Great Western Railway has its full name carved onto the façade (larger than the name of the station). The rebuild also saw a number of other improvements including the lengthening of the platforms, the widening of the Taff River railway bridge to allow the approach lines to the station to be quadrupled, and the installation of colour-light signalling. The rebuild of the station cost the GWR £820,000 (equivalent to £58,640,000 in 2019),, and was formally opened by the then Minister of Transport Oliver Stanley on 26 February 1934.
In July 1934, the GWR began a pioneering diesel railcar service with a buffet between Cardiff General and Birmingham Snow Hill which had only two stops at Newport and Gloucester. This was the first long distance diesel express service in Britain, covering the 117.5 miles (189.1 km) between Cardiff and Birmingham in 2 hours 20 minutes. It proved so successful that larger railcars with more seating and no buffet had to be introduced to cope with demand, and even this had to be augmented by a normal locomotive hauled service. During the Second World War, two such trains ran to and from Cardiff daily. At this time it consisted of a three car train consisting of a standard carriage sandwiched between two railcars, and a stop at Stratford-upon-Avon was introduced.
As a result of representations by the GWR, a nearby working-class district, Temperance Town, was cleared during the late 1930s in order to improve the outlook of the rebuilt station.
In 1992, the station, its entrances and platforms, became Grade II listed.
Cardiff Central railway station