This paper presents the simulated laser absorption coefficient of the radiation fog in the THz regime. The results are obtained based on the effective dielectric constant of the mixture, which is calculated using the Maxwell- Garnett formula in high frequency regime. Our numerical result based on MATLAB simulation suggests that the laser absorption is proportional to the imaginary part of effective dielectric constant, as well as the visibility of the fog. We also calculated the frequency-dependent absorption coefficient, which shows a peak feature at about 5 THz and saturates to a small value at high frequencies.