Pompey were relegated last season and start their bid to climb back to the Championship against their local rivals at Fratton Park on 18 August.
The other two relegated teams start with away games, Doncaster heading to Walsall and Coventry taking on Yeovil at Huish Park.
League Two champions Swindon get one of their longest trips out of the way on the opening day, with Hartlepool their opponents, while Shrewsbury have a daunting trip to Sheffield United.
Crawley, in the third tier of English football for the first time, start out at home to Scunthorpe while play-off winners Crewe host Notts County.
Opening Day fixtures:
Bury v Brentford
Crawley Town v Scunthorpe
Crewe v Notts County
Hartlepool v Swindon
Milton Keynes Dons v Oldham
Portsmouth v Bournemouth
Preston v Colchester
Sheff Utd v Shrewsbury
Stevenage v Carlisle
Tranmere v Leyton Orient
Walsall v Doncaster
Yeovil v Coventry
