The invention discloses a formula and a preparation method of vulcanized fiber paper, and is characterized in that the formula of the vulcanized fiber paper is as follows: the vulcanized fiber paper comprises the components of, by weight, 5-15% of wood pulp, 30-60% of cut pile, and 30-50% cotton linter; the preparation method of the vulcanized fiber paper comprises the steps: the above materials are subjected to stewing, beating and forming paper treatments, then are soaked in a dense zinc chloride solution, and are molded on a gelling machine when being heated to a temperature in a range from 38 DEG C to 50 DEG C; through heating and pressurization by a press roll, fibers are intersected with each other and glued together to synthesize semi-finished product raw vulcanized fiber paper; the raw vulcanized fiber paper is subjected to an ageing treatment in an aging room, then is subjected to a desalination process in a desalination tank which contains zinc chloride, then is washed by clear water to leach out zinc chloride in the inner of the raw vulcanized fiber paper; and finally the raw vulcanized fiber paper is dried in a drying room and shaped by a press machine, and the vulcanized fiber paper is obtained. The vulcanized fiber paper is advantaged in that the vulcanized fiber paper is not liable to generate bending deformation and lose original smoothness; the surface of the vulcanized fiber paper is fine and smooth; and the vulcanized fiber paper does not fade, and has a long service life and a high whole performance.