Magnetic refrigeration is an emerging technology with a great potential of growth, which can substitute, in future, the traditional technology of vapor compression. The refrigerants used by the magnetic refrigerator are not harmful to environment, since they have no Ozone Depletion Potential (ODP) or Global Warming Potential (GWP). This technology exploits the magnetocaloric effect, an intrinsic property of certain materials. This effect is observed in the adiabatic magnetization and demagnetization of the material, with the purpose of creating a temperature differential. The regenerator is composed by this material, and is submitted to four distinct process: magnetization, cold blow, demagnetization and hot blow. This four process, constituting what today is known by active magnetic regenerator cycle, which simulates the Brayton cycle. A device is proposed formed by the gadolinium regenerator , two heat exchangers (a cold and hot one) and a displacer. The device simulates a heat pump, which uses the magnetocaloric effect to create a temperature gradient in the regenerator, so that it can heat or cool the working fluid which exchanges heat at both heat exchangers. An unidimensional model is developed to simulates this device. The principal objective of this work is predict the temperature behaviour across the regenerator, the cooling capacity and the COP of the device. A parameter known as utilization factor is investigated to measure the system efficiency, and how to define this factor is important to improve the device efficiency.A direct comparison between the magnetic refrigeration and vapor compressor refrigeration technologies is carried out. The main parameters for this analysis are: cooling capacity, cost and size.