The invention discloses a preparation method of environment-friendly dyed toilet paper and belongs to the technical field of in-pulp filling. By adopting a dyeing method, natural dye molecules are adsorbed in fibrillated fine fiber or the surface, so that consumption of natural dye is reduced effectively, and production cost is lowered. The toilet paper prepared by adopting the method is high in quality and color fastness, fading of the toilet paper when in use is well avoided, the paper after being dyed is natural and gentle in color tight, the problem of harm caused by synthetic dye and heavy metal to human health and environment is solved, ever-growing spiritual life needs of people are met on the premise that requirements of people on health are met, and color comfort can be brought tousers.