The invention relates to a three-section three-open bamboo cutting board alloy steel die taking phyllostachys pubescens as a raw material and a using method of installing the three-section three-open bamboo cutting board alloy steel die on a supporting production line of a four-post type all-purpose hydraulic machine YA32-315 to perform ordered linkage with an iron hoop forming blank linkage body on compressed bamboo sheets. The die comprises a lower die, a middle die and a three-compound die. The supporting production line comprises a three-compound die hanging frame, a middle die hanging frame, a groove steel guide rail, a mobile working table plate with three working stations, a concave cushion plate, a lower die top column, a middle die top column, a lower die top plate, a middle die top plate and a three-compound die bracket. The die and the production line are in ordered matching linkage, the lower die is meshed with the middle die, and bamboo sheets are squeezed through pressure of 300 tons to enter the iron hoop forming blank linkage body on the three-compound die; after a stable period of 15-20 days, the bamboo sheets are sawn to bamboo cutting boards with different diameter specifications including phi 320, phi 340, phi 360, phi 380, phi 400, phi 420 and phi 450 and with thicknesses of 40 mm, 42 mm, 55 mm and 80 mm. According to the three-section three-open bamboo cutting board alloy steel die, operation workers have easy labor intensity, each shift is 7 hours, there are 2 shifts, 1300 bamboo cutting boards can be produced each day, the products are environmentally friendly, and wood is saved.