The Manchester United midfielder, 30, has not played for his country for 16 months because of his battle with the debilitating condition ulcerative colitis.
However, he has battled his way back to fitness to regain his place in United's starting XI, and now earns his first call since Gordon Strachan took over as manager from Craig Levein 13 months ago.
"It was wonderful over the Christmas period to see him back playing football," Strachan said of Fletcher. "We have got to take it a stage further.
"I've seen him playing and he has lost none of his enthusiasm, which he will never lose. To have him back in the squad is terrific."
Young Dundee United full-back Andrew Robertson has been called up for the first time, and there is a return for Sunderland's Phil Bardsley after a long absence from the international ranks.
Robertson is the only one of the youngsters tipped to feature at the National Stadium in the Polish capital on March 5 to actually make Strachan's squad, with club team-mate Ryan Gauld and Aberdeen pair Peter Pawlett and Mark Reynolds missing out.
"I seen him first game of the season against Partick Thistle and I thought he had something although he was a bit raw and had one or two things to learn," said Strachan.
"So we've kept an eye on him. He joined us in training a couple of months back and we liked what we saw but we won't be putting too much pressure on him."
There is also no place for Kilmarnock striker Kris Boyd or Blackburn's Jordan Rhodes with Strachan only selecting three forwards in his 24-man party.
Goalkeepers: Matt Gilks, David Marshall, Allan McGregor.
Defenders: Phil Bardsley, Christophe Berra, Gordon Greer, Grant Hanley, Alan Hutton, Russell Martin, Andrew Robertson, Steven Whittaker.
Midfielders: Charlie Adam, Ikechi Anya, Barry Bannan, Scott Brown, Chris Burke, Darren Fletcher, James Forrest, James Morrison, Charlie Mulgrew, Robert Snodgrass.
Forwards: Steven Fletcher, Ross McCormack, Steven Naismith.