In this study, powders of manganese ferrite nanoparticles (MnFe2O4) which are having spinel structure was prepared with sol-gel method. In the first part, we have prepared the manganese ferrite nanoparticles with different pH. In the second part of our study, we have studied the effect of reducing the interactions by adding silica (SiO2) to compound. In the third part, we have studied the effect of increasing interactions with apply pressure.In this study, several tools for feature detection is used that includes: 1) X-ray diffraction analysis(XRD)2) infrared spectroscopy analysis (FTIR)3) Thermal analysis of samples (TG-DTA)4)Vibrating Sample Magnetometer(VSM)5) Ac magnetic Susceptibility 6) transmission electron microscopy (TEM ) and 7) field emission scanning electron microscopy (FESEM). Raw materials used in the first part consist of iron and manganese nitrate, citric acid, distilled water and ammonia. The pH of primary solution that combined of raw materials is two, and for preparing the solutions with upper pHs we add ammonia to this solution, so we prepared samples with pHs: 4, 6 and 8. we have observed that the manganese ferrite nanoparticles with pH of 2 treated with interaction superparamagnetism. We have observed that with change of pH the size of the nanoparticles are increased so that for sample with pH of 2 the size of nanoparticles is 6 nm and for another samples the size of nanoparticles is approximately 15 nm. The sample with pH of 2 hasn't any residual but other samples have a little residual. In the second part for injection of silica to the mixture we should prepare another solution. Therefor we made another solution of tetraethyl silica (TEOS) and ethanol and be added to the previous solution. It observed that with adding the silica to compound, interaction between nanoparticles decrease, which was expected. With increasing the nonmagnetic matter (silica) the size of nanoparticles decreased and to this reason observed magnetic properties decreased. As we have seen these samples don't have any residual,so these samples have superparamagnetism behavior, too. In the third part we pressed some of samples with different pressures and we observed, increasing of the pressure, increase the interactions between the nanoparticles and it was expectable. All of the samples pressed without silica have interacting superparamagnetic behavior and with increasing the pressure the size of interactions increase. It observed in the samples with silica that with make of pressure doesn't have more changes in interactions between nanoparticles. This behavior is because that the nanoparticles are floated in the silica lattice and these nanoparticles can't close together and to this reason the interactions between them don't have more change. Key words : Ferrite, Manganese, Superparamagnet, Silica, Press, pH.