Yes, SALMON is a Scrabble word!

Letter values in Scrabble US: S 1, A 1, L 1, M 3, O 1, N 1.

Is it a valid word?

SALMON is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

any of various large food and game fishes of northern waters; usually migrate from salt to fresh water to spawn
a tributary of the Snake River in Idaho
flesh of any of various marine or freshwater fish of the family Salmonidae
a pale pinkish orange color

Also: salmon river, pink-orange, pinkish-orange.