The paper is devoted to the numerical study of the dependence of uniaxial compressive strength of permeable fluid-saturated brittle solids on the loading rate. We analyzed the influence of strain rate, sample size, permeability of the material, fluid viscosity and a coefficient of the influence of pore pressure on the stress state of solid skeleton. We have shown that dynamic values of elastic modulus and strength of the sample is a unique nonlinear sigmoid-like function of the dimensionless parameter that characterizes the ratio of applied strain rate to interstitial fluid flow rate. We proposed the unified approximating function, which describes numerically derived dependences with good accuracy. The results of the study are relevant for estimating and forecasting dynamic compressive strength of the samples of different fluid-saturated brittle solids. Moreover, the proposed expression can be applied to determine unknown values of the fluid effect constants on the basis of reducing the experimental data to a unified curve.