The Yorkshire-based player, who is ranked inside the world's top 400, was forced to come from a set down to defeat America's Stefan Kozlov 4-6, 6-1, 6-3 in front of a near-capacity crowd on No.3 Court.
Enjoying his best run in the junior event at Wimbledon to date, Edmund had to dig deep and utilise all of his reserves to restore parity at one set all against an opponent, who at 15, is three years younger than the Briton.
The teenagers traded breaks at the start of a crucial third set, and as is so often the case, it was the seventh game that ultimately ended up deciding the outcome of the match.
At 0-30 down, Kozlov experienced cramp and paused for a minute before he served, but it appeared as though the wind had been taken out of his sails. Edmund took advantage, broke to love and then held comfortably in the following game.
The British No.13, who currently holds junior doubles titles at the US Open and French Open, then broke the Macedonian-born player's service again to take the set 6-3 and the match.
"It was a tough match. I didn't feel comfortable (being down a set) and I knew that I had to change something, but luckily enough I found some form and really built up my confidence. It was a good match to come through, it's another win and another step closer," said Edmund, who lost to Polish giant, and Andy Murray's semi-final opponent, Jerzy Janowicz in the first round at Wimbledon last week.
The No.5 seed now faces No.6 seed Gianluigi Quinzi of Italy in the semi-finals, after his win over Serbia's Nikola Milojevic.
20:24...But boy, it was a barrow-load of fun. I hope you enjoyed it even half as much as we did. Thank you for all your messages throughout, you've been the glue holding us together as the edges frayed amid the madness. Now if you'll excuse me, it's time for us Brits to raise a toast to Andy Murray and Fred Perry. British sporting legends both.
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