Provided are a unidirectional high-moisture-permeability paper diaper and a making method thereof. The unidirectional high-moisture-permeability paper diaper comprise a paper diaper body, and the paper diaper body comprises a water-permeable inner surface layer, a flow guide layer, an antibacterial healthcare layer, an absorbent core layer and a water-impermeable leak-proof bottom layer which arelaminated in sequence from top to bottom; the water-permeable inner surface layer, the flow guide layer, the antibacterial healthcare layer, the absorbent core layer and the water-impermeable leak-proof bottom layer are made of degradable materials, a plant fiber cloth is adopted as the water-permeable inner surface layer on which an environment-friendly resin film is attached by melting, and theplant fiber cloth is provided with big-end-up funnel-shaped holes. The making materials of the paper diaper can be degraded and recovered, and no harmful chemical substances are used in the processingprocess, so that environmental pollution is small; the environment-friendly resin film which is evenly attached by melting can achieve the effects of reverse osmosis and dryness, and the making material of the resin film has good bacteriostasis and can regulate the pH value of the paper diaper and keep the skin in a comfortable environment; the funnel-shaped holes can effectively guide urine in infiltration and achieve a unidirectional moisture absorption effect.