In this research, manganese ferrite, MnFe₂O₄, nanoparticles with a pure cubic crystalline phase were synthesized by a fast solvent free auto-combustion method using microwave irradiation. Iron (III) nitrate nonahydrate and manganese nitrate hexahydrate as initial materials were mixed together with some organic agent as a fuel and oxidant. Then, the prepared mixture was transferred into a domestic microwave oven with the power of 900 W for 20 minutes.The experimental strong point of this strategy is the use of a simple, low-cost, fastmethod for synthesis of nanomaterialsand also placing in the category of green chemistry reactions.Microstructural studies were done using Fourier transform infrared spectrum (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM). Magnetic hysteresis measurements were performed on a vibrating sample magnetometer (VSM) showing the soft paramagnetic properties of the product.