The disintegration of swelling rocks is the main inducement of engineering disasters, which is influenced by various factors. Grey system correlation analysis is a method of measuring the correlation between factors according to the degree of dissimilarity or similarity of the development trend. The fractal characteristics of swelling rock disintegration were obtained using the calculation method of fractal dimension. Based on the grey system correlation analysis method, the influences of different drying temperatures, different initial mass of single rock and the number of dry–wet cycles on the disintegration of swelling rocks were explored. Through grey system correlation analysis, the correlation of each influencing factor to the fractal dimension of swelling rock disintegration was ranked as the number of dry–wet cycles> the drying temperatures>the initial mass of single block. The results showed that the drying temperatures, the initial mass of single rock, and the number of dry-wet cycles affected disintegration greatly, among which the correlation degree of the number of dry-wet cycles is the greatest.