Salisbury, who won the title with Rajeev Ram a year ago, edged a tight first set tiebreak to defeat Philipp Oswald and Marcus Daniell 7-6, 6-2.
Meanwhile, Murray, who has reunited with former playing partner Bruno Soares for the 2021 season, won 6-3, 6-4 over Marcelo Arevalo and Matwe Middelkoop.
The battle of the Brits looks set to be played out in front of crowds on Rod Laver Arena on Friday after Australian Open officials were given the go head for 50% capacity after the brief Covid-19 lockdown over the past few days.
Of that all-British encounter, Salisbury said: “It’s great that there’s be two Brits in the semis and guaranteed one in the final. The more the better. There’s a bit of rivalry once you play each other but we get on very well and we practise sometimes when we’re back in London.”
Salisbury faces another all-British encounter on Thursday against Murray’s former doubles partner Neal Skupski when he pairs with Desirae Krawczyk in the mixed doubles quarter-finals, with Skupski paired with Andreja Klepac
Murray, whose own mixed doubles ambitions were ended earlier in the week, is bidding for an eighth career Grand Slam title before the end of the week in Melbourne.
Of the Salisbury head to head, he said: “It’s great when the British guys go well. We’re playing to get to a Grand Slam final. The stakes are high. We obviously both want to win.