Wembley has been booked for multiple shows by Canadian pop star The Weeknd on those dates.
The Premier League season is scheduled to begin over the weekend of 22 August, with the Community Shield to be played on 16 August.
The fixture will be played at the home of Welsh rugby for the first time since 2006.
"We are absolutely delighted to be welcoming the FA Community Shield back to Principality Stadium," said Gavin Marshall, chief financial and operating officer of the Welsh Rugby Union.
"This fixture has a special place in the stadium's history, and to be hosting it again for the first time in 20 years is a tremendously proud moment for everyone here."
The venue, which has a capacity of more than 74,000, previously hosted the Community Shield on six occasions between 2001 and 2006 during the redevelopment of Wembley.
The switch to Cardiff may have commercial implications, with Wembley's 90,000-seat capacity and status as the FA's national stadium offering greater match-day revenue and hospitality opportunities.