Although it is believed that rugby had been played in Pontyclun from the early 1880s; a game between a team from Pontyclun and Pentyrch was called off after crowd trouble in 1884, it is thought the rugby club was not created until 1886. The club accepts its creation date as 1887 as proof that Pontyclun played as a RFC during the 1887/88 season, recorded in the Pontypridd Chronicle in November 11 1887. The match was recorded as Pontypridd Juniors against Pontyclown (a common misspelling of the town during the late 1800s) which Pontyclun won. There is also a report in the South Wales Daily News, November 12 1888, of a match between Bridgend and Pontyclown which was news-worthy due to Pontyclun taking offence at the referee, resulting in the team leaving the pitch eight minutes before the end of the match.
In September 1887 Pontyclun RFC applied for membership to the Welsh Rugby Union along with Llandovery, Chepstow and Brecon. The membership was granted in a meeting held at the Queen’s Hotel in Cardiff later that year. Unfortunately for Pontyclun in 1886 the WRU appointed a new secretary, Walter E. Rees, and he brought an element of financial stability to an organisation that was once wasteful. Where clubs were once able to miss membership subscription fees with little reprise, Rees ensured that this was no longer the case and Pontylcun lost their WRU membership in 1888 due to missed subscriptions.
Pontyclun RFC re-applied for Welsh Rugby Union membership in 1919 along with Llanharan and Taffs Well. All three clubs were awarded membership on 22 August of that year, but were told to “put your grounds in order”.
The club first played on a field which is now the site of local school, Ysgol y Pant; until moving to Mill Fields.