With Cardiff almost assured of the title and with both Neath and Llanelli winning in midweek, a victory was needed by the Black and Ambers but despite an entertaining game the home side snatched the two points.
Wing Nathan Daniels scored a try for Newport while fly half Michael Hook added the conversion and a brace of penalties. Alan Williams, Shaun James and Daniel Povey scored tries for the home side while Michael Thomas added two conversions.
Newport are at home to second placed Neath on Tuesday evening (7.30)
A special video package as Pontypridd claimed the double for the first time in their history by winning the Principality Premiership final, including match build-up, highlights, post match reaction and dressing room celebrations.