The invention discloses a room temperature magnetic refrigeration alloy material. The room temperature magnetic refrigeration alloy material is represented by the molecular formula of Mn1-XAlXCoGe; and the alloy material comprises 33.3-34.4% of manganese element, 0.6-2.7% of aluminum element, 32.8-33.3% of cobalt element, and 30.2-32.7% of germanium element in percentage by mass. The invention also provides a preparation method for the room temperature magnetic refrigeration alloy material. The preparation method comprises the steps of adding reactive materials into a vacuum arc furnace, vacuumizing until the pressure is lower than 10<-4>Pa, and pumping argon gas in; smelting the sample repeatedly; and taking out the sample and cooling the sample, putting the sample into a high-temperature-resistant quartz glass tube, vacuumizing, inflating the high-temperature-resistant quartz glass tube with high-purity argon for performing gas washing, then putting the high-temperature-resistant quartz glass tube into a furnace type box, taking the sample out and performing annealing to obtain the room temperature magnetic refrigeration alloy material. According to the preparation method, the Curie temperature of the alloy is obviously reduced to the temperature close to the room temperature, the thermal hysteresis phenomenon occurring close to phase change is effectively avoided, and a relatively wide adjustable temperature range close to the room temperature is obtained.