In this article, we investigate polynomial helices in the n-dimensional semi-Euclidean space with index two for n ≥ 4. We obtain some families of spacelike and timelike polynomial helices. These helices have spacelike or timelike or null axes. After that, we give some examples of the spacelike and the timelike polynomial helices in the n-dimensional semi-Euclidean space with index two for n = 4, 5 and 6