With applications of zinc oxide nanoparticles (ZnONP) continually increasing; however, the neurotoxicity of ZnONP remains unclear. The objective of the present study was to investigate the acute effects of pulmonary exposure to ZnONP on brain. We investigated the effects of ZnONP on behavioral alterations, oxidative stress, inflammation, and tau and autophagy expressions after acute pulmonary exposure. There were no significant alterations in spatial cognition or learning abilities according to the Morris water maze or anxiety according to the elevated-plus maze after ZnONP exposure. We observed that levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG)/dG were significantly increased in the hippocampus after exposure to 10 mg/kg ZnONP. We observed that levels of interleukin (IL)-1β and IL-6 significantly decreased in the cerebellum and cortex after exposure of 10 mg/kg ZnONP. Microglia activation occurred in the hippocampus after exposure. Significant tau expression was observed in the cerebellum and hippocampus with exposure to 10 mg/kg ZnONP, but no significant expressions of beclin 1, light chain 3 (LC3) II/I, or ubiquitin were observed. Results of the present study suggest that acute exposure of ZnONP induced oxidative stress, microglia activation and tau protein expression in brain, leading to neurotoxicity.