This is an excellent hotel. The rooms are large, well appointed, quiet. There is a good coffee shop and a small bar. I have not used the restaurant. Lots of public space to sit around in, and internet access if you need it. It is in the Parc de Nacioes area, which has many restaurants, a large shopping mall, and riverside walks.
It is 5 minutes walk from Oriente station, from where you can travel all over Portugal in either train or bus.
The rates are high but if you book through an agency such as booking.com you can get good offers.
I stay there every time I visit Lisbon, as it is only 5 mins from the airport by taxi.
Highly recommended.

Great hotel!
Rooms are very spacious, modern and with a great decoration! Bed is super comfortable and bathroom is very pretty and clean. Great breakfast too. Just loved it! Amazing value for money! I would say it's one of Lisbon's best kept secrets.
Located in Parque das Nações, it's a bit far from the historical centre, but still it's located in one of the best and most beautiful areas of Lisbon. Very safe and modern area, one step away from Lisbon's Casino and Vasco da Gama shopping centre with cinemas. Also near from dozens of bars and restaurants as well as attractions like Oceanário, Torre Vasco da Gama and Pavilhao do conhecimento. Good links to the metro (Oriente, red line), buses, train (Oriente station) and airport.
Don't miss it!

I am just back from a wonderful weekend in Lisbon, Portugal. The city was in itself fantastic, and the holiday experience did not get less fabulous by staying at the Hotel Olissippo Oriente! The staff was indeed helpful and polite in all ways, everything was spotless (bathroom, the spacious room, etc). I also really enjoyed the breakfast - everything was tastefully arranged, the food was really good, and there was a variety of choices as to what one would like to eat. The area was clean and lovely, transportation facilities were very good, and the hotel was pleasantly close to the airport - which matters if you have to catch an early flight! All in all: I recommend this hotel to everyone!

I have just arrived from Lisbon where i've stayed at Olissipo Oriente. Excelet staff, well equiped rooms decorated with taste, very good breakfast. It is across the street to Lisbon Casino and a 5 minutes walk from Vasco da Gama shopping and train/metro (at gare do oriente). I will definitely return to this hotel.