Curves of mercury injection and pore distribution density of alkali-activated dredged sludge cementation body solidified with fly ash and mineral powder were obtained by mercury intrusion porosimetry (MIP) test, and its shear strength indexes were measured by direct shear test and bearing ratio test. It's proposed to use pore distribution coefficient to characterize the uniformity of pore distribution of the cementation body, and the quantitative relationships between the pore distribution coefficient and the shear strength index and CBR values were established, respectively. The results show that the pore distribution coefficient of the cementation body is closely related to its mechanical indexes. The smaller the pore distribution coefficient is, the more uniformly the pores of the cementation body distributes, and the higher the shear strength index and CBR are, whereas the bigger the pore distribution coefficient is, the less uniformly the pores of the cementation body distributes, and the lower the shear strength index and CBR are.