Pregame ceremonies include a joint honour guard of Newtown police and firefighters, and a moment of silence at which time a list of the victims' names will be recognized on the centre-field scoreboard.
"On opening day, we will reflect upon more important things and the play the game to honour the community of Newtown," Yankees managing general partner Hal Steinbrenner said in a statement. "Since the day of the tragedy, our hearts and thoughts have been with those who were affected."
The Yankees and Red Sox will wear a special ribbon on their uniforms. Baseball commissioner Bud Selig has asked that all other 28 major league teams wear the ribbon during their opening games.
"Months have passed, yet we are still trying to come to grips with this incomprehensible tragedy," Red Sox principal owner John Henry said in a statement. "As our teams look to face each other on opening day, we will stand united in support of the families affected as we remember and honour those who were lost."
Approximately 3,000 people from Newtown will be invited to the ballpark for New York's July 7th game against Baltimore on "Newtown Day at Yankee Stadium."