'I'm so pleased for the supporters we could finish it at home, it's the icing on the cake,' Newport coach Leigh Jones said.
'We've done it through hard work and a good group of youngsters.'
Craig Richards found space out wide for the first try, converted by fly-half Dan Griffiths, and the pair produced the same result soon after to make it 14-0 at the break.
No 8 Rhys Jones stretched Newport's lead soon after the restart, with Sam Waldron, Owen Jones, Scott Williams and Chris Thomas also crossing - Ian Carter claiming Caerphilly's consolation try.
'I'm absolutely delighted for myself, but at times like this coaches get too many plaudits and when things are going badly they get too much criticism,' Jones added.
'It's about the players, backroom staff, office staff, groundstaff and supporters, not the coach.'
Wing Craig Richards bagged a double as Newport led 14-0 at the interval and his side were soon to hear that Cardiff's surprise lead at Neath meant Newport simply had to beat Caerphilly to lead the table by nine points with two matches remaining
Newport, who could boast the best support of any club this season, put the result beyond doubt in the opening move of the second half as No 8 Rhys Jones crossed the Caerphilly line and further tries came from flanker Sam Waldron and replacement backs Owen Jones, Scott Williams and Chris Thomas with Caerphilly centre Ian Carter scoring a consolation effort in a 43-7 scoreline.
Cardiff's splendid effort gained them a 37-27 win at Neath with Nick Macleod scoring 22 of the points, including one of his club's four tries. Matt Allen, Elgan Jones and Liam Roberts completed the scoring.
It was the battle for bottom spot that loomed large after Llandovery had rocked Llanelli 20-11 on Friday evening and there were also problems for Pontypool and Ebbw Vale that left them still biting their nails along.
Pontypool went down to a home defeat by Newbridge 16-12 with wing Mark Addis gaining the only try of the match early in the second half, while Ebbw Vale led 16-10 away to Cross Keys at the interval, but then met a seven-try avalanche to lose 52-30.
Centre Gareth Chapman scored two tries for Keys to take him to 23 for the season, while Darren Miles kicked 17 points.
Pontypridd's Wales under-21 centre Lee Thomas converted seven of his club's eight tries as they won 54-12 at Bedwas with their under-19 flanker Rhys Shellard marking his first senior start with a brace of tries and Matthew Nuthall and Lee Beech also grabbing two apeice.
Bridgend came back to winning ways as they dismissed Aberavon by 39-35 despite Richard Morris gaining his 100th try for the losers, while Swansea led Carmarthen Quins 41-3 at the break, but only just made it 44-33 with Luke Richards scoring 19 points for Swansea.