Possible Duplicate:
Is there a built-in method to compare collections in C#?
What is the best way to compare to generic two generic lists in C# 3.0?
If you want to compare regardless of element order, try the UnorderedEqual<T> method from here:
Otherwise:
var list1 = new List<int> { 1, 2, 3 };
var list2 = new List<int> { 1, 2, 3 };
var areSame = Enumerable.SequenceEqual(list1, list2);