Lisbon has a wealth of world-class museums, from the excellent Calouste Gulbenkian to the outstanding Ancient Art Museum and Orient Museum and there are literally dozens of collections, often housed in former palaces and convents, now open to the public.
Include on your itinerary the Tile Museum and Decorative Arts Museum, together with the Coaches Museum, Maritime Museum, Archaeology Museum and the lavish collections on display inside the Ajuda Palace.
For contemporary Portuguese art, look no further than the Gulbenkian Foundation's Modern Art Centre, the Chiado Museum, and the Arpad Szenes / Vieira da Silva Museum. The Berardo Museum houses one of the world’s largest collections of modern art with works by artists such as Warhol and Picasso, and it offers free entrance.
The local tourist office Lisboa Card provides free access or discounts to most city museums.

For more info click on the links below

Calouste Gulbenkian Museum -
Ancient Art Museum -
Orient Museum -
Decorative Arts Museum -
Coaches Museum -
Maritime Museum -
Archaeology Museum -
Ajuda Palace -
Chiado Museum -
Arpad Szenes Vieira da Silva Museum -
Berardo Museum -