It was the 23rd final between the pair and Littler, who beat Gerwyn Price in the semi-finals, made a fantastic start to race into a 3-0 lead.
Both players showed signs of nerves with a number of errors in a tense opening, and Humphries was able to miss five darts at double and still break back before taking out 130 to level at 3-3.
There was still nothing to separate them at the break – one that seemed to benefit both players as the standard sky-rocketed after the resumption.
Humphries, in particular, came out firing. He broke with an 11-darter and moved two legs clear with a 12-dart hold.
Another 11-darter made it 8-6 and while Littler was holding throw reasonably comfortably, he was unable to put the requisite pressure on the Humphries throw.
There were still nervy moments for Humphries and he went all the way down to double two before moving 10-8 ahead before managing to break once more, finishing on double 10 to clinch victory and take the £275,000 prize money.
For Littler, who edged it 100.29 to 97.86 on the averages, a remarkable campaign that saw him set a points record in the league phase and claim a record six nightly wins ends in disappointment.
It might have been different had he been better on the outer ring, where he was just eight of 27 for 29.6%. Although, Humphries was only fractionally more clinical at 29.7%.
“I had a little bit of a thing after the game – nobody likes losing – but I’m fine,” Littler told Sky Sports.
“I am glad to say the Premier League is over – it’s been a tough 17 weeks. Happy it’s over, and I came runner-up, but I will be back next year.”
Humphries can celebrate coming on top in the latest instalment of a rivalry that looks set to run and run but that will be put on hold soon as Humphries and Littler prepare to team up for England at the World Cup of Darts in Frankfurt in June.
