This study was conducted to investigate the relationship between the climbing up event of Luciola lateralis larvae and water temperature. In the laboratory condition, the larvae did not come out of water at constant temperature condition of 19.3 ± 0.3℃ and tried to climb up at varying temperature condition of 20~22℃ (mean temperature 20.9 ± 0.9℃) without success. However, they climbed up at constant temperature condition of 20.8 ± 0.6℃. The frequency of the larval climbing up was highest as 63.6% at 20~21℃. The most larvae climbed up at approximately 21℃ of average daily water temperature, In the natural condition, the larvae climbed up at 19.8~21.7℃ and the frequency of the larval climbing up was high as 80.4% at 20~21℃. The larval climbing up was also little observed at 19~20℃ at which no larval climbing up was found in the laboratory experiment. No larvae attempted to climb up when water temperature was below 19℃ and above 22℃. It took 18 days from climbing up of larvae to appearance of adults. In its habitat, the range of water temperature required for larvae to climb up is assumed to be 19.6~21.8℃ and the most suitable water temperature may be 20.4 ± 2.3℃. Therefore, the range of water temperature required for larvae to climb up is assumed to be 19.8~21.7℃, and the suitable water temperature range for larvae may be 20~21℃, and the most suitable temperature is thought to be 21℃.