Birrell burst into tears after finally overcoming Oksana Selekhmeteva 6-3 6-7 (4-7) 6-4, with the Melbourne Park clash lasting almost three hours.
Up 5-3, she had two match points but instead lost her serve before regrouping to break her Russian rival to claim the win and the main-draw berth, which will be her ninth Australian Open appearance since 2015.
"I just feel so many things - happy, grateful, relieved and tired," the 26-year-old said in her on-court interview.
Kimberly Birrell needed three sets to beat Russia's Oksana Selekhmeteva in Open qualifying. (James Ross/AAP PHOTOS)
"I love the battle and I knew that was what it going to take to get the win.
"I'm absolutely stoked - I can't wait to play next week.
"I've qualified for a slam before, but it didn't feel anything like this for a home slam, it's just the best feeling."
For the second successive year it appeared the country's No.1 player would miss out on a main-draw spot, with Birrell overlooked for a wildcard that would have secured a start.
Last year then top-ranked Aussie Arina Rodionova slammed Tennis Australia when she was passed over for a wildcard and then lost in qualifying.
Birrell, the world No.99, harboured no ill will over the snub and said she was happy to prove herself in qualifying.
"Wildcards are tricky ones and none of us really deserve them at the end of the day, we're just lucky to come from a grand slam nation, and to have the opportunities that I've had in the past has been unreal," she said at the start of the week.
The Open berth continues a stellar start to the year, with the Queenslander reaching the quarter-finals of a WTA 500-level event for the first time in her injury-ravaged career.
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