The seventh seeds beat three-time mixed doubles winners Tontowi Ahmad and Liliyana Natsir of Indonesia 21-18 21-16 in Birmingham on Friday.
It means the Adcocks become the first British semi-finalists in the competition since 2008.
"We've broken the quarter-final curse that we've had for the last couple of years," said Chris Adcock.
The husband-and-wife pair will meet fifth seeds Joachim Fischer Nielsen and Christinna Pedersen in the semi-finals on Saturday (12:00 GMT), with the match live on the BBC Red Button.
"We've always had that belief in ourselves," said Gabby Adcock. "We are up there and beating the leading pairs."
Chris Adcock added: "To be playing on the Saturday and not watching on television is a great feeling.
"We've gradually played better as the tournament has gone on and right now we're over the moon to play in the semis of our favourite event. We are a bit overwhelmed but it's an amazing feeling."
Earlier, England's Marcus Ellis and Chris Langridge were knocked out in the quarter-finals of the men's doubles.
The pair lost 21-17 22-11 to world number ones Lee Yong Dae and Yoo Yeon Seong of Korea.

Media playback is not supported on this device
The pair, silver medallists at the 2012 Olympics in London, only needed to finish the medal race on Thursday to win gold, and came in eighth.
New Zealand's Jo Aleh and Polly Powrie won silver and Camille Lecointre and Helene Defrance of France took bronze.
Britain have now won 21 gold medals in Rio, and a second in sailing after Giles Scott's win in the men's Finn.
Wales' Mills, 28, and 36-year-old Clark, who comes from Essex, held a 20-point lead going into the medal race after winning three times and never finishing below eighth in the 10 races in the first series.
The medal race had been scheduled to take place on Wednesday, but had been postponed until Thursday because of a lack of wind.
Only a disqualification or technical problem could have denied Mills and Clark, fourth in the world rankings, and they stayed out of trouble as they were eighth out of 10.
Slovenia won the final race but it was not enough to earn them a medal. The United States were in the bronze-medal position until a late mistake dropped them down to last place in the medal race, and seventh overall.
"I can't believe it. It has actually been the best feeling ever," Mills told BBC One.
"We have forgotten all about London. We are so proud to come back after it and we've worked so hard to get the upgrade to gold. Thank you to everyone back home for the support.
"It is all we have ever dreamed of and we are so happy."
Clark added: "The first moment I sailed with Hannah, I knew we could do something special.
"We have been together through ups and downs and been with each other all the way."
Ian Walker, two-time Olympic silver medallist:
"That is thoroughly deserved. Hannah Mills and Saskia Clark have worked tirelessly since silver in London 2012.
"They have eliminated all of their weaknesses and it has all come together here in Rio.
"I don't think we saw the best of Mills and Clark today but they won't care about that and I don't care about that."
Britain have been the most successful nation in sailing in three of the past four Olympics.
The only exception was London 2012, when Sir Ben Ainslie's fourth career Olympic title was his country's only gold of the Games.
Ainslie's Finn class is one area Britain have dominated in recent times, with his three golds in successive Games sandwiched between Scott in Rio and Iain Percy at Sydney 2000.
Mills and Clark's success takes Britain to the top of the Rio sailing medal list, by virtue of Nick Dempsey's silver in the windsurfing, with the Netherlands also winning two golds.
It also means Britain have won 12 Olympic sailing gold medals in the past four Games.
Media playback is not supported on this device
Subscribe to the BBC Sport newsletter to get our pick of news, features and video sent to your inbox.
British duo Chris and Gabby Adcock have reached the All-England Championships semi-finals for the first time.
[NEXT_CONCEPT]
Great Britain's Hannah Mills and Saskia Clark have won gold in the women's 470 sailing event at the 2016 Rio Olympics.