Murray cruised into the last eight with a 6-3 6-1 6-3 victory over Gilles Simon, and next up is another Frenchman in Chardy.
Chardy, the world No 36, beat Murray 6-4 6-4 in Cincinnati last year, and he has already picked up one major scalp in Melbourne, knocking out Juan Martin del Potro.
He booked a shot at Murray by beating Andreas Seppi, and Murray is expecting to be tested.
"Chardy's had two very good wins. He beat Juan Martin Del Potro a couple of rounds ago and I lost to him the last time I played him in Cincinnati, so it will be a tough match," he said.
Murray barely broke sweat against Simon, who was clearly low on energy after edging five-set marathon with Gael Monfils in the previous round.
"I have to try and focus on my side of the court. He's one of the best movers on the tour and he was clearly struggling in his movement today," Murray said.
"It was tough, but that's what Grand Slam tennis is. The games are so physical nowadays and it was 8-6 in the fifth set the other day and nearly five hours, so it was tough for him."