The invention discloses a smoke agent used for preventing and treating cancer and diabetes mellitus and a method for preparing electronic smoke of the smoke agent. Firstly, tobacco essence distilled water serves as a liquid solvent, and mineral microelements such as iodine, rubidium, chromium, manganese, vanadium, strontium, nickel, boron, silicon, iron, arsenic, molybdenum, selenium, silver, copper, titanium, platinum, zinc, cobalt, germanium, fluorine and tungsten are added in the tobacco essence distilled water; a microelement ionic liquid smoke agent is prepared after an ionization and ultrasonic technology and device are adopted for conducting ion dissolution; then the liquid smoke agent is put into an electronic pulverization smoking set to be atomized; atomized smoke agent ionic gas enters a smoke outlet pipe; finally, a user inhales the smoke agent gas into the oral cavity and the lung cavity in a smoking manner through a smoking method, and the smoke agent gas enters a blood circulation system of the human body; at last, the human immune system function is regulated and improved through the microelement ionic smoke agent, and therefore the effects and the aims of preventing and treating the cancer and the diabetes mellitus are achieved.