The invention relates to a technological method for preparing environment-friendly rubber filling oil. The method is characterized in that third-cut distillate oil is used as raw material oil, N-methyl pyrrolidone is used as a solvent to perform the solvent extract, and the influence of the extract temperature and a solvent-to-oil ratio on the property of the raffinate oil is examined. The acid-alkali refining is performed for the raffinate oil, the influence of the solvent-to-oil ratio on the refined oil is examined, and the raffinate oil stands for a given period of time until non-ideal components are completely settled. The method is simple in operation and low in investment expense, the obtained environment-friendly rubber oil is high in yield, the content of polycyclic aromatic hydrocarbon is smaller than 3.0 percent, the acid-alkali refining can improve the color, smell and safety of the oil product, and the research and development prospect is promising.