The synthesis and the characterization of mesostructured silica doped with acidic acyl-hydroxy-pyrazoles like extractants are described. The extractants have either a single chelating site, 1-phenyl-3-methyl-4-stearoyl-5-hydroxy-pyrazole (HPMSP), or two chelating sites, 1,12-bis(10-phenyl-30-methyl-50-hydroxy-40-pyrazolyl)-dodecane-1,12-dion e (HL-10-LH). The so-called doped silicas were synthesized in basic medium according to a sol-gel process beginning with the solubilization of the extractant in a micellar phase followed by the precipitation of silica around micelles. The chemical composition of the synthesized materials, especially the ligand content, was determined. High quantities of ligand loadings (up to 0.69 mol/kg) are reached. The materials obtained were characterized by X-ray diffraction, laser granulometry, transmission and scanning electron microscopy and, after calcination, by nitrogen physisorption. Un-doped silica is mesostructured, lamellar, and has high pore diameter as well as high specific surfaces. Doping induces the disorganization of the lamellar structure, the increase of the pore diameter, and a slight decrease of the specific surface. The capacities of extraction of Cu(II) and Eu(III) by the doped materials and the corresponding extraction rate were measured: high values are reached.