Montmorillonite K- 10 is widely used in organic reactions, belongs to the class K- catalysts derived from a mineral aluminum hydrosilicate. K- 10 has a structure in the form of “sandwich “in which an octahedral layer (Al) is sandwiched between two tetrahedral (Si). The Montmorillonite, K10, has used as catalyst in organic reactions in processes where acids are used as catalysts Lewis or Brönsted. Another application is their use as solid support anchoring reagents such as Clayfen and Claycop oxidants, impregnated with metals such as Fe3 +, Zn 2 + , Co 2 +, used as a catalyst in condensation reactions in MCR 's and currently proline as bifunctional catalyst. It is worth noting the possibility of using the K10 reactions associated with various forms of energy, reflux in organic solvents in microwave or ultrasound and given the precepts of green chemistry in reactions without solvents. Several synthetic routes and interconversion of functional groups are focused as transesterification, halogenation, oxidation combined with the classic reactions of aromatic acylation and alkylation, Diels Alder and rearrangements leading heterocyclic systems such as Pyrazoles, Isoxazoles, Isoquinolines, Pyrazolones and Isoxazolonas . All these properties and applications highlight the versatility of the K-10 as solid support in organic reactions. Keywords: montmorillonite, solid support, K10, heterocyclic compounds, enamino compounds