Careful control of (i) the hydrolysis of Ta(C2H5)(5) in ethanolic solution and (ii) of the pillaring process allows the synthesis of a stable tantalum pillared montmorillonite (Ta PILC). This solid presents a basal spacing of 26 Angstrom after calcination at 500 degrees C. The surface area and the microporosity were evaluated by N-2 adsorption isotherms and through the alpha(s)-plot method.