Norway doesn't use the Euro. In fact it isn't even a member of the European Union, though it is in the EEA (European Economic Are) so it has important ties with the rest of Europe. It is active in the single market and has social and military as well as business links with the EU.

The currency of Norway is the Krone or NOK. At the moment the exchange rate is about 1 NOK to 1.33 Euros, but you can get the latest exchange rates here. It is better to exchange money and get some Krone before you go to Norway, but in fact the Euro is mostly accepted in the larger cities and the bigger tourist attractions. This isn't 100% though, which is why you should have Krone too. Most major credit cards are accepted too, but again you need to have currency just in case.

You can find out more about visiting Norway here.