Abstract: Acoustic communication is one of the most important means of communication in anurans. The call behavior of many male frogs has a circadian rhythm that is affected by temperature and relative humidity. In this study, the calls of 61 males of Rhacophorus rhodopus were collected from May to June 2016. We investigated the call structure and circadian variations of calling patterns and their relationship with air temperature and relative humidity over 22 days. The results showed that R. rhodopus had two basic call types: monosyllabic and multisyllabic calls (note number 2-20, with an average of 6.27±2.94). There were no fundamental frequency differences between monosyllabic calls (212.51±21.63 Hz) and multisyllabic calls (225.39±26.80 Hz). The note duration, dominant frequency, and internote interval of monosyllabic calls (16.93±1.68 ms, 2289.87±120.14 Hz, 610.99±178.48 ms, respectively) were greater than those of multisyllabic calls (14.83±1.27 ms, 2213.32±106.95 Hz, 60.66±8.56 ms, respectively). Male R. rhodopus called from 19:00 to 03:00 every night, with a peak at about 22:00. The results showed that R. rhodopus communicated more efficiently by changing the dominant frequency, note number and internote interval. The calling behavior of R. rhodopus was affected by air temperature and relative humidity to a certain extent.