The cheap flights airline will introduce the two new services from January 2009, departing from Lisbon on Fridays and Saturdays.
Flights will depart on both days from Lisbon at 23:25 and will arrive in Oslo at 04:25, according to local time on the Friday.
The return flights will depart from the Norwegian capital at 05:10 landing in the Portuguese base at 08:20 on both Saturday and Sunday.
TAP recently announced that it will begin offering flights between Lisbon and the city of Casablanca in Morocco.
This brings the carrier’s total number of routes to African cities to nine. The airline also offers services to Bissau, Dakar, Luanda, Maputo, Johannesburg, Sal, Praia and Sao Tome.
TAP has also announced that it intends to increase the number of passengers it takes into the African continent by more than 150,000 by the end of 2008.