Aza heterocyclic compounds are major interest for organic chemists because of their mainly pharmacological activities and clinical applications such as antianxiety, antitumor, anticonvulsant, cardiotonic and vasorelaxant. This work a new and efficient synthesis of phthalazine drivatives from the three-component condensation reaction of malononitrile, phthalhydrazide and aromatic aldehydes using MCM-41 as catalyst. The features of this procedure are mild reaction conditions, good to excellent yields, short reaction times and operational simplicity.Mesoporous solids synthesized using micelles as structure directing agents have been found to posses’ large specific surface area, large pore volume, regular order of pore structure and tuneable pore characteristics Recently, the discovery of a new family of mesoporous molecular sieves designated as MCM-41 has been reported by researchers at the Mobil Corporation . The MCM-41 material possesses a uniform hexagonal array of cylindrical pores embedded within a silica-based matrix. The material is synthesized through a hydrothermal reaction of silicate gel in the presence of a surfactant.