The northernmost point in Scandinavia is in Norway.
For the Scandinavian Peninsula, the northernmost point is Cape Nordkinn, also called Kinnarodden, on Norway’s Finnmark coast. The cape reaches farther north than Sweden or Finland and is recognized as the northernmost point of mainland Norway and mainland Europe.
This question can cause confusion because “Scandinavia” is used in more than one way. In its narrow cultural sense, Scandinavia usually means Norway, Sweden and Denmark. The Scandinavian Peninsula is a related geographical term covering most of Norway and Sweden and part of northwestern Finland. Under either common interpretation, Norway is the accepted country answer.
Norway’s famous North Cape, or Nordkapp, is often advertised as Europe’s northernmost point, but it is not the true northernmost point of the mainland. Knivskjellodden, on the nearby island of Magerøya, extends farther north than Nordkapp, while Cape Nordkinn is farther north still when discussing mainland Europe. Including Norway’s Svalbard archipelago creates a separate island-based distinction.