This study evaluated stress experienced by rescue team members during a simulated search and rescue operation in a confined space and determine if wireless communication reduces stress. A total of 57 rescue team members of X prefecture participated. The stress visualization indices were ptyalin (i.e., salivary amylase), salivary cortisol, autonomic nervous system response, visual analog scale, and a short version of the Profile of Mood States. The subjects were randomized to perform a simulated search in a confined space without or with communication, and the stress indices were compared between the two groups.Stress was observed in the form of changes in ptyalin level, visual analog scale scores including impression of the subjects, and autonomic nervous system responses. Statistical analysis showed that the “with communication” group exhibited significantly lower stress than the “without communication” group. Thus, wireless communication is recommended to reduce the stress experienced by rescue team members working in confined spaces.