Abstract: The inhaled nanoparticles (NPs) are first met by the biological barrier inside the alveolus known as the lung surfactant (LS). They can reach deep into the lung and interfere with the biophysical properties of the lung components. The interaction mechanisms of the gold nanoparticles (AuNPs) with the LS monolayer and the consequences of the interactions on the lung function are not well understood. Coarse-grained molecular dynamics simulations are carried out to study the interaction between the AuNPs and the LS monolayers at the nanoscale. It is observed that the presence of the AuNPs deforms the monolayer structure, changes the biophysical properties of the LS monolayer, and the results also indicate that the AuNPs with different shapes have different effects on the LS monolayer. These findings could help to identify the possible consequence of the airborne NPs inhalation.