Thec atalytic activity of supported silver nanoparticles on mesoporous silica was studied, for the selectiver eduction of azines into benzyl hydrazones using sodium borohydride as mild reducing agent. Different sizes of silver nanoparticles supported on mesoporous silica (Ag/HMS) were successfully prepared by two methods,i .e., wet impregnationf ollowed by reductionw ith hydrogena t3 50 8 8Ca nd in situ deposition/reduction with am ixture of amines (ethanolamine and ethylenediamine).T he Ag/HMS (amines) catalyst was found to promote the selective 1,2-reduction of aryl-substituted azines, comparedt o the corresponding 1,4-reductiont hat occurs in general reduction processes. This catalytic transfer hydrogenation process found to be clean, fast andq uantitative (> 99% yields and selectivity) towards benzyl hydrazone synthesis under mild conditions.O fg reat importance is that under the presentc atalytic condi-tions reducible functional groups remain intact. Formal kinetics, support the in situ formation of silver hydride species being responsible for the reductionp rocess.T he presence of protic polarm ethanol enhanced the catalytic activity of Ag/HMS. Basedo nt he recycling studies the catalytic system Ag/HMS-NaBH 4 wasf ound to catalyze the selective reductiono fa zines nine times without significant loss of its activity.F inally,ao ne-pot reactionb etween the in situ produced benzylh ydrazones and a series of nitrostyrenes readilyp rovided the regioselective synthesiso f1 ,3,5-subtituted pyrazoles,h ighlightingau seful synthetic application of the catalytic protocol.