High-quality asphalt with a composite modifier is necessary for the high-grade pavement to meet the requirements. In this study, nano-organic palygorskite (O-PAL) was successfully prepared by acid activation and silane modification. O-PAL, together with styrene-butadiene-styrene block copolymer (SBS) modified asphalt, was prepared by melt blending. O-PAL composite SBS modified asphalt can form a multi-phase homogeneous system with a spinodal strengthened structure, which can improve the properties of asphalt. 3 wt% O-PAL composite SBS modified asphalt showed excellent water stability; and the critical temperature of the modified asphalt increased up to 40% by adding O-PAL. O-PAL can not only reduce the aging of the asphalt matrix but also reduce the thermal decomposition oxidation of linear SBS. The anti-aging and storage stability performance of the composite modified asphalt is also improved by the addition of O-Pal. O-PAL and SBS are quite a good combination for modified asphalt in high-temperature and humid areas. (C) 2020 Elsevier B.V. All rights reserved.