The invention discloses meal replacement powder capable of reinforcing the kidney, invigorating the heart and reducing weight and a preparation method of the meal replacement powder. The meal replacement powder capable of reinforcing the kidney, invigorating the heart and reducing weight comprises the following raw materials in parts by weight of 20-50 parts of soy protein isolate, 15-35 parts ofrefined and coarse grain powder, 5-25 parts of fruit powder, 2-15 parts of other herb, 1-10 parts of chia seeds, 15-30 parts of erythrite, 2-10 parts of composite mineral substances, and 0.1-0.6 partof complex vitamins. According to the meal replacement powder, the soy protein isolate, the refined and coarse grain powder, the fruit powder, the other herb, the chia seeds, the erythrite and the like are used as raw materials, so that the meal replacement powder has the efficacy of being good in mouth feel, low in heat quantity, balanced in nutrients, healthy, safe and good in satiety, has the efficacy of reinforcing the kidney and invigorating the heart, is free from essence, pigment, preservatives, cane sugar and artificial sweeteners, is convenient to carry and eat, can be used as meal replacement foods for people suffering from obesity, high blood pressure, high blood lipid, high blood sugar, and sub health, and besides, is suitable for thin crowds to be eaten as snacks except threemeals.