A coloring of PG(n, q), the n-dimensional projective geometry over GF(q), is an assignment of colors to all lines of PG(n, q) so that any two lines with the same color do not intersect. The chromatic index of PG(n, q), denoted by χ ′ (PG(n, q)), is the least number of colors for which a coloring of PG(n, q) exists. This paper translates the problem of determining the chromatic index of PG(n, q) to the problem of examining the existences of PG(3, q) and PG(4, q) with certain properties. As applications, it is shown that for any odd integer n and q ∈ {3, 4, 8}, χ ′ (PG(n, q)) = n 1 q , which implies the existence of a parallelism of PG(n, q) for any odd integer n and q ∈ {3, 4, 8}.