The world number four was pushed all the way as Joyce took three sets in what was ultimately a losing effort, with Littler eventually coming out on top in a 4-3 victory.
The 17-year-old averaged 103.14 and hit an eye-catching 14 180s, but struggled to finish off his opponent and missed several doubles with a highest checkout of just 68.
“It was a very tough game. We both played very well,” reflected Littler.
“Ryan said he had no power-scoring, but he was right behind me in every leg I won! Ryan won’t be happy with the result, but I think he should be happy with the way he played."
Littler will now face stablemate Nathan Aspinall in the quarter-finals as he vies for his first World Championship title.
“I’m expecting Nathan to play very well. We’ve played each other many times before, we know how we can play.
“This is the quarter-final of the World Championship, so may the best man win on the day!”
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