The trio have been absent for much of the season and their comebacks could not be more timely, with the Magpies 13th in the Premier League but just four points above the relegation zone.
Chris Hughton, who along with Colin Calderwood is in charge of team affairs following boss Joe Kinnear's heart surgery, told the club's official website: ''Oba Martins, Alan Smith and Mark Viduka will all be fit to make an impact in the run-in and that's a good boost for us.
''It's very important to have them back in the frame. It's immensely beneficial to us - they could be very important for us in the coming weeks.''
Australia striker Viduka has been limited to five appearances all season by an Achilles problem but came off the bench for the final 10 minutes of the 3-2 defeat of West Brom at The Hawthorns as Newcastle ended a winless run of eight matches.
Nigeria striker Martins has been out since mid-December with a hernia, while England international Smith has had foot and ankle problems and has not featured this term.
Hughton believes the presence of three seasoned internationals will benefit the entire squad, even if they are not fully fit.
''The group of lads we've got, they'll look around them and see senior, quality and experienced players with them,'' he added. ''Even if they are not quite up to full fitness, the lift they give the rest of the lads is obvious.
''Alan Smith has played in two friendlies and will play in the next one, while Oba will have had some training under his belt by the time of the next match.''
Brazil international defender Claudio Cacapa is also making progress in training, having been unavailable in 2009 due to a knee injury.
''Among the minuses there are plenty of pluses,'' added Hughton.
Meanwhile, the caretaker boss could call for back-up while leading Newcastle in Joe Kinnear's absence alongside Colin Calderwood.
''We're both coaches who are used to the training pitch,'' the 50-year-old told the Northern Echo. ''There will be some parts of training that I will take and some that Colin will take, but on the Saturday I will be the manager and he will be assisting me.
''He's a good person for me to lean on because he's had managerial experience, but if at any stage we felt we needed to bring someone in, we would. But the only reason we would do that is to cover.
''We feel that we're okay at the moment, but we wouldn't hesitate to do it if we felt like we needed another body to perhaps do some individual work. We wouldn't hesitate to do that.''