Bioaerosols come from a wide range of sources, which have been implicated to be associated with respiratory diseases. In general, bioaerosols include viruses; bacteria and endotoxins; actinomycete; fungal spores, glucans, and mycotoxins; algal and plant cells; insects and mites (their fragments and. excreta); and proteins from birds and mammals. In this report, the basic characteristics, health effects, concentration distributions, and future research direction of bioaerosols are investigated Because Taiwan is located in a subtropical area with high temperature and relative humidity throughout the year, bioaerosols show grow easily and quickly in Taiwan. Therefore, it is very necessary and important to futher evaluate bioaerosols and their health effects.