The invention discloses an environment-friendly type biological activity quick vegetation establishment soil engineering material for a slag-hill-protected slope. The soil engineering material is of a composite structure. According to the structural sequence, the soil engineering material comprises an upper three-dimensional soil engineering plastic net, an upper plant fiber layer, a nutritive layer with seeds, a lower plant fiber layer and a lower three-dimensional soil engineering plastic net in sequence from top to bottom. The upper plant fiber layer, the nutritive layer with the seeds and the lower plant fiber layer are woven to be shaped through degradable plastic wires, the upper three-dimensional soil engineering plastic net and the lower three-dimensional soil engineering plastic net. The soil engineering material is used for covering the slag-hill-protected slope; ecological restoration and landscape planting are conducted on the slag-hill-protected slope; the effects that water is retained, soil moisture is preserved, and rain wash is prevented are achieved; and by means of an activated sludge layer inside the soil engineering material, nutrition can be provided for initial growth of plant seeds, so that vegetation is formed quickly. The soil engineering material has the beneficial effects of being low in cost, great in adaptability, simple in engineering operation and the like; and water-soil conservation and vegetation greening of an ore slag hill can be achieved quickly.