The 19-year-old Spaniard revealed he suffered a muscle injury in his right leg during pre-season training.
Writing on social media Alcaraz said: "It's time to deal with another blow. When I was at my best in pre-season, I picked up an injury through a chance, unnatural movement in training.
"I'd worked so hard to get to my best level for Australia but unfortunately I won't be able to play the Care A2+ Kooyong (warm-up event) or the Australian Open. It's tough, but I have to be optimistic, recover and look forward. See you in 2024 @australianopen."
Alcaraz surged to the top of the rankings in a remarkable 2022 season, becoming the youngest man ever to hold the number one position after beating Casper Ruud in the final in New York.
The teenager suffered a blow at the end of the campaign when he tore an abdominal muscle, forcing him to miss the ATP Finals and the Davis Cup Finals.
The timing of this latest injury is extremely unfortunate and robs the Australian Open of one of its most exciting drawcards.
Alcaraz's absence means his compatriot Rafael Nadal is set to be top seed for the defence of his title at Melbourne Park, with the tournament beginning on January 16.