Brazil are in London that week and are playing Argentina at Arsenal's new Emirates Stadium on September 3rd.
Early discussions took place between the countries regarding a friendly as Wales were free that midweek. After going quiet for a while the Brazilians in the last 48 hours announced the game was on and it has appeared in FIFA's fixture list.
Wales play the Czech Republic in Teplice on Saturday September 2nd.
Wales last played Brazil at the Millennium Stadium 6 years ago and lost 3 - 0. The only Welsh victory in 9 attempts was in 1991 when Dean Saunders scored the only goal at the Arms Park.