In this investigation, polymeric hydrogels with inclusions of magnetic nanoparticles (NPMs) were synthesized by reverse microemulsion polymerization method. Two stages were considered; the synthesis of the NPMs and the structuring of the hydrogel functionalized with the NPMs. A factorial design was used with 27 treatments with two replicates each, analyzing the influence of three factors: polymer concentration, melting temperature and homogenization time on the degree of saturation of the resulting hydrogels. Concentrations of 0.04, 0.05 and 0.06% by mass of agarose, combined at 50, 60 and 70°C for intervals of 7, 10 and 15 minutes were considered for homogenization. The samples were characterized by IR spectroscopy, scanning electron microscopy and refractometry; the presence of functional groups such as hydroxyl with a peak at 3311.18cm-1, at 709cm-1 the Fe-O-Fe bond of hematite and the characteristic peak of agarose at 994.125cm-1, attributed to the 3,6 anhydrous galactose bond. In addition, the homogeneous distribution presented by the NPMs around the hydrogel could be observed. The best results were obtained when applying the medium level of treatment (0.05% agarose), providing an average Brix percentage of 69.59%. It is concluded that the hydrogel synthesized is chemically stable, with a homogeneous distribution of NPMs in its structure, which do not saturate the sample, allowing the possibility of its subsequent use in the carriage of substances.