The American joined sister Venus in the last four after stepping up a level to oust the dangerous Briton 6-2, 6-3 on Rod Laver Arena and end her nine-match winning streak.
Her battling victory keeps intact a potential all-Williams final, with Venus needing to get past fellow American Coco Vandeweghe in the other semi-final to set-up the nostalgic showdown.
But first Serena must beat former teenage prodigy Mirjana Lucic-Baroni, who upset fifth seed Karolina Pliskova to continue her heart-warming comeback after her career was derailed by personal issues.
“She played so well, she’s definitely a future champion here for sure,” Williams said of ninth-seeded Konta. “I’m really happy to get through that.
“I got a little frustrated, but I told myself, stop complaining. Don’t be ‘Baby-rena’. I admit I complain a lot. That’s my thing. I try to just have fun, and try to enjoy the moment out here.”
The victory over Konta, who had been in impeccable touch heading into the match, marked an incredible 10th successive Grand Slam semi-final for Williams, and her 34th overall, reinforcing the 35-year-old’s remarkable consistency.
She has refused to talk about the possibility of finally surpassing Steffi Graf to win a 23rd Grand Slam and take sole ownership of the Open-era record.
But Williams now has a real chance of doing so to further cement her place as perhaps the greatest player of all time.
If she achieves the goal of winning a seventh Australian Open, it will also propel her back to world number one, after Angelique Kerber snatched the accolade from her last year.