Djokovic, who like Federer is bidding for a record seventh title in Melbourne, will play a qualifier in round one.
Third-seeded Caroline Wozniacki, who won her first Grand Slam title here previous year after a tough final against Halep, is in the same section as Maria Sharapova and has Petra Kvitova at the top of her quarter.
Serb Djokovic could then face a rematch of his 2008 final triumph over Frenchman Jo-Wilfried Tsonga in the second round, before a possible second week match-up against Japan's Kei Nishikori in the quarter-finals.More news: Athletics Expect Heisman Winner Kyler Murray To Enter NFL Draft
"I always enjoy my matches against him", 20-time grand slam victor Federer said at the draw.
Alex de Minaur, the only Australian men's seed in the draw at number 27, opens against Pedro Sousa, while other prominent first-round matchups for the locals include John Millman against Federico Delbonis, and Nick Kyrgios in a mouth-watering encounter against big-serving Canadian Milos Raonic, the 16th seed.
Fourth seed Osaka faces Poland's Magda Linette first up and may need to battle past twice champion Victoria Azarenka in the third round.
"I can't believe it's been a year already", Dane Wozniacki said at the draw ceremony.More news: England rugby chief Simon Kemp makes 'significant changes' revelation after injury rise
Murray played at the season-opening Brisbane International last week, where he won his first-round match against James Duckworth but lost in straight sets to Daniil Medvedev in the second, limping between points and admitting he's still dealing with his troublesome right hip.
"To finally get that (title) here was so special, it's the happy slam".
British number two Heather Watson takes on 31st seed Petra Martic from Croatia while Katie Boulter, playing in her first slam main draw outside of Wimbledon, meets experienced Russian Ekaterina Makarova.
For more sports coverage, visit the ABS-CBN Sports website.More news: Blood moon to grace Vancouver skies January 20