The invention discloses a portable fire scene environment detection device. The device comprises a fixing plate, wherein an expansion device is arranged in the fixing plate; the device can be worn on the head of a user when the expansion device is expanded, and can be stored for high portability when the expansion device is retracted; a through hole is formed in the fixing plate in a vertically penetrating manner; a detection box is arranged in the through hole in a sliding manner; and a cooling device is arranged in the detection box, and can be propped against the top of the head and cool the top of the head. The portable fire scene environment detection device has the advantages that the size is small, so that high portability is achieved; the device can be quickly worn on the head during use, so that the wind direction in a fire scene can be monitored, and people can be guided to quickly escape to an exit; and the smoke content in air can be monitored, and the people can be reminded to crawl through an alarm to avoid inhalation of smoke.