The 35-year-old central defender was suspended for the 2-2 home draw against Oman in March, which left the Socceroos in danger of missing out on direct qualification for Brazil next year.
Although currently without a club, Neill had worked hard at a recent training camp with Australia-based players, Osieck said.
"It's always a concern when a player doesn't play regularly," the German said.
"But he's still the captain of the team and to have him around still has some value."
Also returning is Josh Kennedy, who plays in Japan for Nagoya Grampus Eight and is one of the few Australia players who could be described as an out-and-out striker.
There was no place for club-less forward Harry Kewell.
The Oman draw, achieved only after Tim Cahill had orchestrated a comeback from 2-0 down, left Australia third in Asian Group B behind Japan and Jordan with only the top two guaranteed a spot at the 2014 finals.
That makes at least a draw in the away match against runaway group leaders Japan on June 4 in Tokyo highly desirable to allow for any more potential slip-ups in their final two fixtures at home to Jordan and Iraq on June 11 and 18.
"We're not going there as tourists, that's for sure," Osieck said in an interview on the Socceroos website.
"We definitely have to do a lot better against Japan, we have to be more aggressive, we have to play more into their defensive third and I'm pretty confident the boys who will be on the pitch will."
Osieck, who coached in Japan for three years at the Urawa Reds, said he would "regulate" his players to ensure they did not fall into the trap of thinking they could afford to drop points in Tokyo.
He will also be looking for a better display from his defence than in the Oman match to counter the attacking threat of the likes of Manchester United's Shinji Kagawa, VfB Stuttgart's Shinji Okazaki and Nuremberg's Hiroshi Kiyotake.
"They play very aggressively forward when they play at home," Osieck added.
"They have some excellent players, particularly when you look at Kagawa, but even the other boys, they play regularly in the Bundesliga. Yeah, they are pretty strong in that area, and it will be a big challenge for us.
Mark Bresciano, Alex Brosque, Tim Cahill, Robert Cornthwaite, Ivan Franjic, Eugene Galekovic, James Holland, Brett Holman, Mile Jedinak, Josh Kennedy, Robbie Kruse, Mitchell Langerak, Ryan McGowan, Matthew McKay, Mark Milligan, Lucas Neill, Jade North, Tommy Oar, Sasa Ognenovski, Tom Rogic, Mark Schwarzer, Archie Thompson, Michael Thwaite, Dario Vidosic, Luke Wilkshire, Michael Zullo