Abstract: For finite-difference time-domain (FDTD) scheme in simulation of electromagnetic wave propagation in Cole-Cole dispersive media. Several improvements are made:(1) preserving a term with static ionic conductivity in Cole-Cole model, which is fit for real Cole-Cole media; (2) extending to three-dimensional (3-D) case; (3) selecting parameters of human breast tissues from experiment. Feasibility and validity of the scheme is preliminarily demonstrated by numerical examples. The modified scheme is propitious to wave propagation in general Cole-Cole dispersive media.