The present study investigates the effect of solid state grinding of meloxicam as a model of poorly water-soluble drug with hydrophilic polymer hydroxypropyl methylcelluloce (HPMC) 6 cps by using ball milling machine on dissolution rate of meloxicam. The ratio of meloxicam to HPMC were 1:1, 1:3, and 1:5. The solid state interaction of co-ground and physical mixture was evaluated by X-raypowder diffraction, thermal DTA, and SEM. The dissolution studies were conducted in USP type II apparatus. The result of X-raypowder diffraction analysis showed that the co-ground of meloxicam with HPMC decreased the drug crystallinity. The endothermic peak of meloxicam from co-ground products shifted to lower temperature and peak intensity decreased significantly. X-ray powder diffraction and DTA analysis showedthe transformation of crystalline state of meloxicam to amorphous one by cogrinding with HPMC. SEM results showedthe co-ground mixture has agglomerate form.The highest in dissolution rate was observed with co-ground products of meloxicam and HPMC (ratio 1:3) compared to the intact meloxicam, ground meloxicam and its physical mixture.