  In this talk, we review a QCD factorization based approach to extract parton
distribution and correlation functions from lattice QCD calculation of single
hadron matrix elements of quark-gluon operators. We argue that although the
lattice QCD calculations are done in the Euclidean space, the nonperturbative
collinear behavior of the matrix elements are the same as that in the Minkowski
space, and could be systematically factorized into parton distribution
functions with infrared safe matching coefficients. The matching coefficients
can be calculated perturbatively by applying the factorization formalism on to
asymptotic partonic states.
