1. A method for making a snack box, which is characterized in that it takes corn wrapped leaves as the main raw material and sequentially completes the steps of cooking, fiber extraction, warp spinning, weaving, prepressing, cutting, molding, hot pressing, trimming, inspection, sterilization, packaging and warehousing. Wherein: a, the cooking step is to soak the selected raw material corn wrap leaves in a high-temperature and high-pressure container. B, fiber lifting step: the raw materials soaked, boiled, decomposed and softened in step a are put into a fiber carding machine to comb out fibers, the linear speed of the carding roller is controlled at 500-600 m/min, the fiber length is controlled at 30-50 mm, and foreign flowers are discharged from an impurity discharge port; C, the warp spinning step is to spin the fibers extracted in step b into warp yarns on a twisting machine, and the coarseness is controlled at 0.5-0.6mm; D, the weaving process is to weave the raw materials after the c process into sheets by weft yarns. Between 2000 and 2500. E, preloading the warp knitted fabric in step d, and controlling the pressure between 0. 1-0. 15Mpa. Holes, seams and gaps in woven materials are bridged and flattened by preloading; F, the cutting process is to cut and blank the pre-pressed materials in the e process according to the shape of the lunch box; G, the molding step is to put the molding material cut in the step f into a mold, and stretch and position it; H, hot pressing: putting the parison positioned in the step g into a hot press for hot pressing, wherein the hot pressing temperature is150-170 DEG C, the unit pressure is 2.5-3.5 MPa, the time is 25-35 seconds, and the parison is taken out after hot pressing; 1. The trimming step is to trim the residual edge of the semi-finished product formed by hot pressing in the H step; J. The inspection process is to inspect the quality of finished products after trimming in the I process, and transfer the qualified products with no leakage, no scars, flat appearance and smooth surface to the next process; K, the sterilization process is to put the qualified products in the J process into a sterilization cabinet for sterilization and disinfection, so as to reach the hygienic standard; 1. The packaging technology adopts transparent film bags, each bag is subcontracted by 20 or 150, and the outer packaging carton is subcontracted by 200 or 500, and put into storage.