Abstract: For epidemic situation of SARS-CoV-2, computational fluid dynamics method was used to simulate the problem of respiratory droplets transmission in the airflow between the patient and healthy person with anti-droplet face shield. The two dimensional unsteady incompressible Reynolds average N-S equations were solved to obtain the mean flow field. The computational domain was discretized by structural grid technology and H-grid topology. The turbulence fluctuation was described by the RNG k-ε turbulence model. The dispersed phase of droplet was treated as continuous fluid by Euler model. The influence of spraying speed, diameter and inlet content of the respiratory droplets on the transmission in the airflow was obtained. The concentration distribution of droplets along the horizontal and vertical transmission line were analyzed. It shows that, the spraying speed and the inlet content are positively correlated with the transmission speed and concentration distribution of the respiratory droplets, while the effect of diameter is mainly reflected in the influence on the peak concentration. The transmission mechanism of respiratory droplets in the airflow is firstly dominated by the convection, and later by the diffusion, which will form a droplets cloud. The anti-droplets face shield can’t protect the respiratory droplet transmission unless the breathing mask is used for physical isolation from droplets, due tu he fact that: the vortex will transport respiratory droplets into the anti-droplets face shield.