Cocrystal is a relatively new solid form of activepharmaceutical ingredient that offers an alternativeplatform in improving physicochemical properties ofactive pharmaceutical ingredients Padrela et al.,2009; Mashhadi et al., 2004. Cocrystal is defined asa stoichiometric multi-component system connectedby non-covalent interactions where all thecomponents neutral and solid under ambientconditions Thakuria et al., 2013. Cocrystal can beconstructed through interaction hydrogen bonding,pi-stacking, and van der Waals forces Mashhadi etal., 2004. A pharmaceutical cocrystal is composed ofan API and an appropriate coformer as carboxylicacids and amides Qiao et al., 2011.Cocrystallization of active pharmaceutical ingredientis an opportunity for enhancement of importantphysiochemical properties of an activepharmaceutical ingredient without changing itsmolecular structure Maeno et al., 2014.Atorvastatin Calcium (AC), ([(R-(R*,R*)]-2-(4-fluorophenyl)-beta, delta-dihydroxy-5-(1-methylethyl)-3-phenyl-4-[(phenylamino)carbonyl]-1H-pyrrole-1-heptanoic acid), calcium salt (2:1)trihydrate ([C33H34FN2O5]2Ca.3H2O), is considered asone of the most effective of synthetic lipid loweringagent Shete et al., 2010. The drug is orally used toreduce of total cholesterol, low density lipoproteinand triglycerides Anwar et al., 2011. There are 42crystalline structures of AC Shayanfar et al., 2013.However, chance to create AC into another crystalstructure to improving physicochemical properties ofAC is still fully open Chadha et al., 2012.In the present study, we explored cocrystallization ofAC by solvent evaporation method. This study aimedto confirm whether AC was able to form cocrystalwith malonic acid (MA) as coformer. AC-MAcocrystal was prepared by solvent evaporationmethod by using methanol as solvent.Characterization of cocrystal was done by powder Xraydiffractometry (PXRD), differential scanningcalorimetry (DSC), fourier transform infrared (FTIR)spectroscopy and scanning electron microscopy(SEM).