The invention discloses an experimental synthesis method and device of an active iron-sulfur compound. The method comprises the following steps of: uniformly placing reactant solids on a laminated glass plate in a pressure-resistant quartz pipe, spraying a proper amount of deionized water on the surface of the reactant solids to wet the reactant solids, and sealing the pressure-resistant quartz pipe through an end cover; connecting the air inlet end of the pressure-resistant quartz pipe to an H2S gas bottle, introducing H2S gas into the pressure-resistant quartz pipe, discharging internal airby using the air outlet end of the pressure-resistant quartz pipe, and stopping introducing of the H2S gas after adjusting the pressure to a certain value and stabilizing; completely reacting the reactant solids and the H2S gas under the closed pressure in the pressure-resistant quartz pipe to generate a required active iron-sulfur compound sample. The method and the device can simulate the formation process of an actual active iron and sulfur compound on site to the greatest extent, provide active samples with high spontaneous combustion tendency and high efficiency, and have far-reaching influence on subsequent research.