Due to abnormal weather caused by global warming, sleep disorders due to the hot and humid conditions in the hot season are regarded as a problem, and a means to obtain a healthy sleeping environment in the summer is desired to prevent human error. In this study, it was investigated effect of ice slurry intake and positively lowered the core body temperature at the time of falling asleep to verify that it led to falling asleep. Seven female and one male participated in this study. They ingested ice slurry before falling asleep. The purpose of this study was to investigate effect of pre-cooling by ice slurry intake before their own sleeping. It was examined whether the quality of sleep was improved by the ratio of non-REM sleep time by wearable sensors. It was recorded the situation in which the quality such as temperature and humidity in their own sleeping room. Also sleep time was comprehensively evaluated in each sleep environment of the subjects. The obtained deep sleep time was not predominant in the presence or absence of ice slurry before falling asleep. There were 411 night sleeps in this study. There was no significant difference between ice slurry sleep and control sleep. However, as a result of individuals, there was a tendency for long-term deep sleep due to ice slurry inoculation.