The invention discloses a preparation method of tangerine leaf process soap, which is characterized in that the extracted veins of tangerine leaf are used as a carrier of soap and dip-coated with crystal soap liquid containing medical stone component, and a two-dimensional code image-text layer containing bamboo charcoal component is printed thereon. The whole preparation method comprises the steps of tangerine leaf processing, discoloration treatment, soap liquid dip-coating, image-text preparation and quality test and packing. The method disclosed by the invention solves the shortcomings of great waste and inconvenience in carrying of the existing bulk fancy soap, realizes the functions of discoloration and prevention of skin disease, greatly improves the interest and practicability of fancy soap, and is a pioneering innovative product bringing benefits to tangerine farmers, which not only can widen the rural employment channel, but also can provide a new means of turning waste into wealth and increasing income of tangerine farmers and make a contribution to the construction of harmonious new countryside.