The invention relates to a tobacco leaf and a green mould proof method of products thereof, which is characterized in that after raw tobacco leaves are packed by a corrugated case provided with a plastic inner liner, or packed and sealed cigarette finished product packing boxes are directly irradiated by ray with the dosage of 4kGy-10kGy, so that the aims of killing and preventing mould can be achieved. The invention has the advantages that electron accelerator irradiation technology is adopted and is easy to combine with the existing tobacco processing technique, and irradiation can be taken as a working procedure in the process flow of the tobacco processing technique; an electron accelerator is directly installed in a flow line of tobacco processing, so that automation is easy to realize; the ray generated by the electron accelerator has higher energy and can penetrate the cigarette boxes, so as to rapidly and thoroughly kill the mould in the tobacco leaves and the products thereof with high efficiency for once, reduce mildew loss, and lower the administrative expense on a tobacco barn; furthermore, the ray can kill pests in tobacco storage, accelerate the alcoholization of the tobacco leaves, and improve the suck quality of the tobacco leaves, so that the invention has practicability; in addition, the invention opens up a new path for preventing mould of the tobacco, thus having considerable market prospect.