The AC Milan full-back was hurt during Thursday's training session and was taken to a nearby hospital to have an MRI scan.
Though De Sciglio will miss the Group D opener in Manaus, he is expected to recover in time for the clash with Costa Rica on June 20.
"Defender Mattia De Sciglio, after today's (Thursday) training session in Portobello (Mangaritiba), has sustained a muscle strain in his left thigh," Italy team doctor Enrico Castellacci said.
"The player underwent an MRI at Angra dos Reis this afternoon and the test has revealed an oedema in his left femoral biceps.
"De Sciglio will not be available for the first game against England."
Italy coach Cesare Prandelli is unlikely to replace De Sciglio, despite having taken Inter Milan defender Andrea Ranocchia as a reserve player to Brazil.
The Azzurri can make a substitution because of an injury 24 hours prior to their first World Cup game.
Prandelli will have the rest of his players available after Paris Saint-Germain midfielder Marco Verratti recovered from flu.
The Italians travel to Manaus on Friday morning and will train at the Amazonia Arena later that day, the venue for Saturday's encounter.
It's a pity he'll miss out, after the season Milan had to have 3 players in the squad is pretty good. Italy have a good mix of young players with experience from Buffon, Barzagli, De Rossi and Pirlo, it could be that they surprise a few teams- shea666