Key words：Chiroptera, roost, echolocation call, acoustic monitoring, acoustic index Bats are characterized by high species and ecological diversity. They also provide several important ecosystem services, including pollination, seed dispersal, and insect pest suppression. Since bats usually can react to anthropogenic disturbances quickly and are sensitive to environmental changes, they have been suggested as effective bio-indicators to environmental conditions. Therefore, to secure bat diversity and the associated services to human wellbeing, it is necessary to monitor the distribution and population dynamics of bat species. With diverse terrain, climatic conditions and landscapes, the Taroko National Park supports rich mountainous fauna and flora. However, our knowledge of species diversity and the spatio-temporal variations of chiropteran fauna is still limited. To date, 25 species belong to 16 genera of 5 families have been reported by the SWAN in 2016, indicating a rich bat fauna in the park. Therefore, it is essential to develop adequate survey tools to further investigate the dynamics of bat populations and communities. In the present project, we aim to (1) continuously surveying bats for a more comprehensive understanding of chiropteran species diversity and the spatio-temporal patterns of the species distribution, (2) acquiring species trait data, (3) collecting and understanding the echolocation call diversity, and (4) evaluating the potential of acoustic technique and acoustic indices in estimating spationtemporal variation of bat activities. We surveyed bats along the eastern section of the Central High Way at low (<1100 m asl), medium (1100~2200 m asl), and high (> 2200 m asl) elevation ranges for four seasons. Multiple techniques were used, including mist netting, harp trapping, bat detectors, roost surveys, and interviewing local people, to maximize our understanding of bat diversity. Three external traits and releasing calls were collected from captured individuals. We also set up stationary bat detectors at 3 forest sites along the elevation gradient and 2 roost sites to monitor bat activities for at least one week in each survey season. Bat calls, call features, and 6 acoustic indices were extracted and measured from the sound recordings automatically using R language-coded tools. In this year, we recorded 18 bat species, including 8 species and 1 subspecies endemic to Taiwan. We also got the first occurrence record of Harpiocephulus harpia, Tadarida insignis in the low elevation region, the first record of Hipposideros armiger in the middle elevation region, and records of two rare species, namely Plecotus taivanus and Barbasetella darjelinensis in the park. Among all roosts surveyed, the NingAng Bridge tunnels were the most important reproduction sites for H. armiger and Rhinolophus monoceros in the park. Noteworthy, most our records of roosts of Pipistrellus montanus and Murina puta were reported by national park staff and local people, suggesting the potential of citizen science in gathering wildlife species occurrence information. We found the 19 selected call feathers are effectively in distinguishing calls from 13 species in our collection. For acoustic monitoring, we found both call abundance and acoustic indices varying among sites and seasons for all sampling sites. Based on the roost site data, call abundance and values of the temporal entropy index had significant correlations with the monthly counts of bat individuals inside the roosts. Our results show that acoustic techniques are potentially effective in monitoring the diversity and abundance of bats in Taroko National Park.