Presented here is a study of the large p_T J/ production in double pomeron exchange processes via gluon fragmentation at hadron colliders. We use three sets of parametrization (hard gluon, hard quark, and soft gluon) for the parton distribution in the pomeron to estimate the production cross section. We find that the J/ production rate is sensitive to the gluon component of the pomeron. Especially, at the LHC the soft gluon parametrization gives the J/ production rate two order of magnitude larger than that hard gluon parametrization gives.