Phthalhydrazide-functionalized MCM-41 (P-MCM-41) was prepared and characterized, and its catalytic activity was evaluated. MCM-41 and 3-chloropropyl trimethylsilyl-MCM-41 (CPS-MCM-41) were prepared according to methods previously reported in the literature. Then CPS-MCM-41 was reacted with phthalhydrazide to yield the desired catalyst. The obtained base catalyst was characterized using SEM, EDX, XRD and FT-IR. No leaching problem was observed after several runs, while the catalyst was recovered and reused without a loss of reactivity under the described reaction conditions. Phthalhydrazide-functionalized MCM-41 was employed as a reusable base catalyst for the synthesis of coumarin-fused triazolopyrimidines via a three-component condensation of 4-hydroxycoumarin, 3-amino-1H-1,2,4-triazole and aromatic aldehydes.