If it is pouring down outside, when you are visiting a museum, you do not want to have to go searching for a place to have a snack or lunch break. Sseveral museums offer very nice cafés or restaurants.

The National Museum (Nationalmuseet) 

On the first floor you will find a very nice restaurant with tables 'indoors' and on the 'terrace' overlooking the entrance hall.
Nationalmuseet
Events at Nationalmuseet

Glyptoteket - vinterhavenNy Carlsberg Glyptotek

Tables are set on a balcony overlooking the glass roofed palm gardens (see photo) complete with neo-classical statues and fountains.  The French inspired dishes are all home made and are prepared as you wait.
Ny Carlsberg Glyptotek 
Events at Ny Carlsberg Glyptotek

Statens Museum for Kunst - skulpturThe National Gallery (Statens Museum for Kunst) 

The Danish National Gallery has had a major facelift and as part of the new building project completed in 1998, a restaurant has been added.  Among other things they offer special meals for children.
Statens Museum for Kunst 
Events at Statens Museum for Kunst

Danish Museum of Art and Design (Kunstindustrimuseet) 

The Museum of Decorative Art continues its theme into its café, which is furnished in classic style by Danish designers, Hans J.Wegner and Paul Kjærholm.
Kunstindustrimuseet
Events at Kunstindustrimuseet 

Ordrupgaard

The Ordrupgaard Museum reopened its new addition designed by Zaha Hadid, the Iraqui, London based architect in August 2005. Here the café is run by Paul Cunningham, who is also in charge of 'The Paul' a prestigious Michelin starred restaurant in Tivoli. Ordrupgaard is noted for its fine collection of Impressionist art.
Ordrupgaard 
Events at Ordrupgaard

Den sorte diamantThe Royal Library (The Black Diamond) 

Overlooking the old canals, furnished in a fine, minimalistic style is the Restaurant Søren K named after the famous Danish philosopher and author Søren Kierkegaard. A very nice place to have a restful meal in splendid surroundings.
The Royal Library 
Events at The Royal Library