Abstract: The coefficients b,ρ, and σ in Born-Mayer-Huggins potential were determined empirically for three interactions in CaF_2 system. The potential suggested in this work have reproduced the experimental lattice energy, bulk modulus, and three elastic constant very well. The radial distribution functions for molten calcium fluoride have been given by molecular dynamics simulation with the potential obtained. The results show that there is a great deal of difference in the three radial distribution functions. The first peak of radial distribution function is very sharp in the cation-anion case and smoothing down in the cation-cation and anion-anion case. The maximum of g_(--)(r) distribution is not high and a limp point appears between the first peak and the first valley of g_(--)(r) curve. The distances where the radial distribution function g_(+-)(r) has a maximum are 0.225 nm for T=2000 K and 0.221 nm for T=2200 K. These values are less than 0.2357 nm, the distance between cation and anion in crystalline phase of calcium fluoride, that indicates there are some "holes" and chain-like structures in molten system.