This paper proposes preliminary work to study the diffusion and migration of chloride ions in cement pastes at early age. The non-steady state ion migration coefficients of cement pastes are evaluated from three aspects: (1) electrical rapid ion migration test; (2) non-contact impedance measurement (NCIM) based on a fractal model; and (3) a corresponding simulation of an "I" shape fractal network. The experimental results from electrical rapid ion migration tests and NCIM have good agreement. The influences of water to cement ratio, curing hydration age and addition of mineral admixtures on the performance of ion diffusion/migration in cement pastes are investigated.