The loess-paleosol sequence contains rich climate change information during formation process. A typical loess-paleosol sequence was selected to analyze the grain-size, magnetic susceptibility and element intensity of samples. Fractal method was used to describe the characteristics of grain-size distribution and evaluate the relationship between fractal dimension and pedogenesis process. Based on the results of the mass balance and soil reconstruction model, the relationship between loess deposition and pedogenesis was studied. Change of unary fractal dimensions was consistent with the changing trend of climate indicators, and average fractal dimensions of paleosol (2.246) was greater than that of loess (2.201). The fractal dimension can evaluate the fragmentation degree of particles and magnitude of energy events. Results of piecewise linear regression analysis showed that there were two different fragmentation mechanisms in the process of particle fragmentation. DF1 was close to 3, and the energy dissipation in the process of coarse particles breaking into fine particles was mainly manifested in volume; DF2 was close to 2, and the energy in the process of breaking fine particles into clay particles mainly proceeded along a two-dimensional plane. The volume changes of loess and paleosol were simultaneously affected by pedogenesis, formation pressure and global climate. The mass loss or gain shown by the different size-fraction components and element intensity indicated that the loess deposition and pedogenesis were simultaneous. During the prevailing summer monsoon, strong pedogenesis was dominant and formed paleosol. While the cold-dry climate during the prevailing winter monsoon promoted the loess deposition. The fractal and reconstruction model respectively quantitatively calculated the degree of particle fragmentation and the amount and process of material change during the formation process of loess-paleosol. Their combined application can enrich the theory of soil genesis and help to understand the origin of loess-paleosol sequence and its relationship with climate change.