The results obtained in many experimental data show that the effect of turbulent diffusion on the performance of an electrostatic precipitator (ESP) is significant. The ways of handling the turbulent diffusion effect in different efficiency models are different. The effects of turbulent diffusion modeling on ESP performance models are investigated by comparing various models which include plug, Deutsch, Cooperman, Leonard‐Mitchner‐Self (L‐M‐S), and 2nd‐order closure models. The results obtained show that the largest difference of the estimation values of collection efficiency between various models in the range 0–10000 cm2/s of diffusivity is about 28%. When the diffusivity is less than 300 cm2/s, thex‐direction diffusion effect makes no obvious contribution to collecting process but they‐direction diffusion effect makes a marked contribution. When the diffusivity is larger than 300 cm2/s, the uncollected particles are mixed well in they‐direction and the influence ofx‐direction diffusion effect on collection efficiency becomes sensitive with the increase in diffusivity. Moreover, it is shown that the collection efficiency decreases when the entrance concentration increases. When the flow velocity is small, the migration velocity increases with increasing flow velocity. This anomalous phenomenon can be explained by the ionic wind effect, and the case studies show that there exists a maximum collection efficiency when the flow velocity is about a half of the ionic wind velocity.