To understand the impact of ambient temperature on dispersal of global COVID-19 pandemic in a better way, we investigated the relationship between daily confirmed cases and maximum/minimum temperatures. It was observed that most of the daily COVID-19 cases were located in regions with maximum temperature range of 5 °C to 30 °C. A similar study by Triplett (2020) indicated that the rate of confirmed COVID-19 cases will be significantly reduced when maximum temperature reaches above 22.5 °C. Moreover, the cases were mainly concentrated in regions with minimum temperature range of 0 °C to 15 °C. It is well known that large daily temperature difference may easily trigger influenza. Therefore, we investigated the relationship between daily confirmed cases and temperature difference. The results showed that rapid increase in the number of COVID-19 cases was associated with a daily temperature difference threshold of 8 °C and the number of cases decreased when daily temperature difference was greater than 8 °C. These results indicated that there was a nonlinear association between confirmed cases of COVID-19 and daily temperature difference.