Keggin-type phosphotungstic acid (H3PW12 O-40, PTA) encapsulated in the mesocages of chromium-based terephthalate metal-organic framework (MIL-101) was established to be an active heterogeneous catalyst for three component Biginelli condensation reaction with excellent yields (75-90%) and selectivity under solvent free condition. Here phosphotungstic acid can be effectively incorporated into the matrix of MIL-101 by an impregnation method. The synthesized PTA@MIL-101 was characterized by employing various spectroscopic techniques as well as different analytical methods. Moreover, the catalyst could easily be recovered and recycled without any significant loss of its catalytic activity. (C) 2015 Elsevier B.V. All rights reserved.