Effect of organic monotmorillon on performance,storage stability,SHRP technical performance of SBS-modified asphalt was investigated.Test results show that when content of SBS is 5%(by mass) in SBS-modified asphalt by adding a certain amount of organic monotmorillonite,the SBS-modified asphalt that is stable in storage can be obtained.Its conventional technical performance meets the requirement set forth in polymer modified asphalt SBS category I-D technical specification,and is better than that without organic monotmorillonite in the SBS-modified asphalt,SHRP technical performance accords with PG70-22 technical requirements.The mechanism of improvement by organic monotmorillonite in the SBS-modified asphalt is analyzed.