The invention relates to an efficient and environment-friendly rubber-powder-modified asphalt waterproof coiled material and a preparing method. The preparing method comprises the steps of mixing anduniformly stirring 34-54 parts of matrix asphalt and 1.5-15 parts of softening oil, increasing the temperature to 150-170 DEG C, starting to add 10-15 parts of waste rubber powder and 0.01-0.03 part of an activating agent, increasing the temperature, maintaining the temperature at 170-180 DEG C, conducting development for 60-80 minutes at the rotation speed of 20-200 r / min, afterwards, adding 4-15parts of waste rubber powder, conducting stirring development for 10-20 minutes, conducting cutting and grinding once through a colloid mill, adding 15-30 parts of a filler, and then conducting stirring development for 30-60 minutes to obtain a modified asphalt coating material; conducting coating and cladding technologies on the prepared modified asphalt coating material, and then conducting cooling rolling to prepare the rubber-powder-modified asphalt waterproof coiled material. According to the efficient and environment-friendly rubber-powder-modified asphalt waterproof coiled material andthe preparing method, by adding the activating agent, all technology parameters of the batching period are greatly adjusted, the technology time can be shortened, the technology temperature and stirring speed can be lowered, and the prepared product also has better performance indexes, has excellent storage stability and application performance, and is an efficient, energy-saving and environment-friendly product.