Acrylamide based nearly mono-disperse polymer microgels including poly(N-isopropylacrylamide-co-acrylamide) and Poly(N-isopropylacrylamide-acrylic acid-acrylamide) with different feed compositions were synthesized using precipitation polymerization in aqueous medium. These microgels were used as micro-reactors to fabricate silver nanoparticles by chemical reduction of silver ions inside the polymer network. The pure and hybrid microgels were characterized by using Fourier transform infra-red spectroscopy (FTIR), UV Visible spectroscopy (UV Vis), Dynamic light scattering (DLS), X-ray diffraction (XRD), Thermogravimetric analysis (TGA), Differential scanning calorimetry (DSC), Scanning electron microscopy (SEM), Energy Dispersive X-ray (EDX),Transmission electron microscopy (TEM) and Scanning transmission electron microscopy (STEM). Ag contents in the hybrid system were determined by ICP-OES. Results revealed that spherical silver nanoparticles having diameter of 10-20 nm were successfully fabricated within the microgels with hydrodynamic diameter of 250±50 nm. The uniformly loaded silver nanoparticles were found to be stable for long time due to donor-acceptor interaction between amide groups of polymer network and silver nanoparticles. Catalytic activity of the hybrid systems was initially tested by choosing catalytic reduction of 4-nitrophenol as a model reaction under various conditions of catalyst dose and concentration of NaBH4 at room temperature in aqueous medium to explore the insights of catalysis process. The progress of the reaction was monitored by UV Visible Spectrophotometry. The pseudo first order kinetic model was employed to evaluate the apparent rate constant of the reaction. It was found that the value of apparent constant increases with increase of catalyst dose due to increase of surface area as a result of increase of number of nanoparticles. The Ag- poly(N-isopropylacrylamide-co-acrylamide) hybrid microgels were found to be temperature sensitive and Ag-Poly(N-isopropylacrylamide-acrylic acid-acrylamide) hybrid microgels both temperature and pH sensitive in aqueous medium. Ag-Poly(N-isopropylacrylamide-acrylic acid-acrylamide) hybrid microgels have long term stability under various conditions of pH of the medium. The hybrid microgels were used as catalysts for simultaneous reduction of various nitro compounds in aqueous medium. Nitroarenes like o-nitroaniline (o-NA), p-nitroaniline (p-NA), p-nitrophenol (p-NP) and nitrobenzene (NB) were individually and simultaneously reduced to corresponding amino-aromatic compounds by sodium borohydride in the presence of Ag-Poly(N-isopropylacrylamide-acrylic acid-acrylamide) hybrid microgels catalyst. Catalytic activity of the hybrid microgels for individual and simultaneous reduction of nitroarenes was compared with each other. The retardation in catalytic reduction of each nitroarene in the presence of other nitroarenes was explained on the basis of simultaneous adsorption. Various factors affecting the catalytic reduction of p-nitroaniline (p-NA) like catalyst dose and pH of the medium were also investigated. Rate of reduction of p-nitroaniline was found to be increased with increase of catalyst dose and pH of the medium. Various nitroarenes were successfully converted into their respective aromatic amines with good to excellent yields (ranging from 75% to 97%) under mild reaction conditions in the presence of Ag-Poly(N-isopropylacrylamide-acrylic acid-acrylamide) and Pd-Poly(N-isopropylacrylamide-acrylic acid-acrylamide) hybrid microgels. The catalyst has ability to successfully convert substituted nitroarenes into desired products keeping many functionalities intact. Pd-Poly(N-isopropylacrylamide-acrylic acid-acrylamide) hybrid microgels were also found to active for a variety of Suzuki coupling reaction. The catalyst can be stored for long time without any sign of aggregation and can be used multiple times without any significant loss in its catalytic activity.