The invention belongs to the technical field of coal bed methane exploration and development and particularly relates to an artificial coal core as well as a preparation method and application thereof. The artificial coal core comprises the following components in percentage by weight: 85-90% of coal particles, 5-10% of sodium bentonite and 5-10% of water. According to the artificial coal core provided by the invention, the composition is closer to that of a natural core, and the effect of a core flow test is better. The materials mainly include coal particles, sodium bentonite and water at a moderate proportion, the composition conforms to the composition of real coal, and some properties such as matrix pores and interfacial tension of coal particles in the original sample of coal are maintained; during a test, the fluid is in direct contact with the coal and sodium bentonite; and the artificial coal core is more real than the existing artificial core bonded with quartz sand epoxy resin.