Walcott was injured in the opening minutes of Friday's 5-0 win over San Marino after a collision with goalkeeper Aldo Simoncini.
"Theo Walcott has been ruled out of the FIFA World Cup qualifier with Poland on Tuesday with a chest injury," said the Football Association in a statement.
The statement continued: "The Arsenal forward was taken to hospital following a collision with the San Marino goalkeeper on Friday night, he was monitored overnight as a precaution and following scan results today will return to his club for further treatment."
England, perhaps shaken by Walcott's injury, took 35 minutes to break the minnows down with stand-in skipper Wayne Rooney opening the scoring from the spot.
He added another in the second half with Danny Welbeck scoring twice and Alex Oxlade-Chamberlain adding the fifth to give the scoreline a truer reflection of England's total domination of the match.
Rooney took his goal tally for England to 31 to make him their fifth highest scorer of all time.
"I'm extremely proud to be in England's top five scorers. But I am only 26 and I hope I can score a lot more," the Manchester United striker said afterwards.
While Rooney was heading up the charts, Oxlade-Chamberlain, 19, entered them, scoring his first international goal to become England's fourth youngest scorer behind Rooney, Michael Owen and Tommy Lawton.
Oxlade-Chamberlain's father Mark Chamberlain was a former England international and the young Arsenal player said afterwards his father had been chiding him about not scoring for England in his first seven games.
"It's a relief to get the monkey off my back, as they say. I have been looking for my first goal for England and my dad's been pushing me, telling me I needed a goal."
The victory put England top of Group H with seven points from three games followed by Montenegro and Poland both on four points from two matches.
England will face a far harder task in Warsaw on Tuesday, Poland warming up for that game with a 1-0 home win over South Africa in a friendly on Friday where Marcin Komorowski scored the only goal after 81 minutes.
- Wayne Rooney
- Theo Walcott