The direct insertion of niobium(V) and zirconium (IV) into the ordered cubic pores of Ia3d mesoporous silica, KIT-6, was performed by employing a hydrothermal method and utilizing a versatile structure directing agent, Pluronic P123 triblock copolymer, in n-butanol as co-solvent. The effect of simultaneous incorporation of niobium and zirconium on the acidity of KIT-6 nanomaterial was investigated and compared to Nb-KIT-6 and Zr-KIT-6. The prepared mesoporous Nb-Zr/KIT-6 was characterized by N-2 porosimetry, TEM, FESEM, XRD, NH3-TPD, FT-IR, and ICP-OES. Results displayed that niobium and zirconium ions were well incorporated into the KIT-6 framework and the entire ordered pore structure has been retained. Incorporation of niobium and zirconium ions enhanced the catalytic activity of KIT-6 as strong acid sites. Eventually, the synthesized Nb-Zr/KIT-6 was used as an effective, recyclable and green catalyst for the multi-component, one-pot production of some substituted benzylpyrazolyl coumarins via condensation of phenylhydrazine, ethyl acetoacetate, 4-hydroxycoumarin and various aldehydes under mild solvent-free conditions with fair to excellent yields.