The victory meant Pontypridd finished the league 23 points clear of Llandovery in second while despite defeat, Llanelli did enough to earn a play-off semi-final trip to take on the Drovers.
In the early stages of Saturday's game, Pontypridd's first foray into opposition territory earned a points reward as outside half Simon Humberstone stroked over a penalty with barely a minute gone. Llanelli responded with some brilliant phases of support play though, moving the ball wide for full back Dale Ford to cruise in for a try which was converted by Jordan Williams.
The game was evenly balanced but Pontypridd seized an opportunity to counter from broken play, Humberstone darting over for a try which he himself converted. Errors were being committed by both teams, which hampered their genuine attacking intent.
But it wasn't long before Llanelli duly drew level as outside half Williams converted a penalty with 22 minutes gone.
And things soon got better for them, Wales Under 20 flanker Dan Thomas breaking clear to gallop over for a try wide out.
The game was ebbing and flowing and with Llanelli scrum half Justin James sent to the sin bin, Pontypridd were giving everything to breach their opponents' defensive line.
Initially there was no breakthrough but when winger Chris Clayton set off on a run, the home side finally gathered momentum down the flank to send back rower Ed Siggery over for a try which Humberstone converted from a wide angle.
The score meant Pontypridd boasted an interval lead of 17-15.
Llanelli were first on the scoreboard as the second half got underway, outside half Williams on target with a penalty attempt.
With the visitors back into a one point lead, it was a series of mauls and drives that got Pontypridd back on track, then turning pressure into points as Humberstone dummied and broke off the back of a strong scrum to cross for his second converted try of the day.
The contest remained close fought into its final quarter, Pontypridd showing good support skills and kicking for field position to remain in the ascendancy.
And when Humberstone added a late penalty, it was enough to secure yet another win.
Pontypridd will now face either Llandovery or Llanelli in the Premiership play-off final on May 18.