The 23-year-old becomes only the sixth British man to reach the semifinal of a Grand Slam event and he will be crowned the new British number one if he advances to the final.
Marin Cilic awaits for the Next Gen star after the Croatian profited from a retirement at two sets all in his encounter with Rafael Nadal.
“It is an amazing feeling,” beamed Edmund courtside.
“With these sorts of things you’re so emotionally engaged that you don’t really take it in, you don’t enjoy yourself, so just at the end, after a hard march and having played lots of matches so far, I just really tried to enjoy the moment."
The Brit had lost a tight three-setter against Dimitrov in Brisbane earlier this month and he has been playing lights-out tennis since that disappointment.
The Bulgarian emerged from an emotionally-charged victory over Nick Kyrgios in the previous round but he was at sixes and sevens during the early exchanges.
Edmund broke in the opening service game as the Bulgarian’s serve faltered and he lost only one point on his serve through four games.
They were back on serve almost immediately, however, with Dimitrov beginning to crank up the pressure and Edmund, through a double-fault, starting to realize the occasion.
But the Bulgarian failed to carry the momentum and he lost his serve in the ninth game, salvaging the first of two break points before Edmund got hold of a timid second serve out wide and crushed it down the line.
He was forced to save break points of his own before closing out the first set in 43 minutes.
Dimitrov was able to fashion a response, breaking for a 2-0 lead and looking much more assured when faced with pressure. Triple break point was wiped in the following service game and he salvaged a break opportunity to hold for 5-2.
A set point arrived for the Bulgarian and he leveled the contest when Edmund looped a forehand return into the net.
Dimitrov had encountered similar resistance in his third round meeting with Andrey Rublev earlier in the tournament and as the third set developed so did the feeling that whoever grabbed the vital break would run away with the match.
And it arrived for the Brit at the most pleasing moment, with the Bulgarian dumping a short second serve into the net on break point. Inevitable, it seemed, after landing only 39% of his first serves in the set.
Edmund, after keeping his cool to close out the set, was a set away from a watershed victory and he seized the advantage when he broke Dimitrov for a 3-2 buffer in set four.
Parity was briefly restored as Edmund failed to solidify his break of serve but Dimitrov buckled under pressure in the ninth game, netting a routine backhand on break point to gift the 23-year-old the opportunity of a lifetime.
He needed no second invitations, although he did require the assistance of Hawk-Eye, to seal the victory.
“I had a little blip in the fourth set but held my nerve in that last game and just prayed the last ball was out,” said Edmund after the win. Destiny awaits.