Abstract: In order to discover the function of model experiment in studying underground coal gasification,the paper stated structure features,combustion area expansi on law and gasification technique of an experiment gasifier in underground coal gasification model. The study results showed that though the model gasifier could not fully simulate a deposition condition of the underground seam,but could set up temperature,pressure,component,stress and other measuring points in the seam and rock strata and could obtain the measured temperature field,pressure field,concentration filed,stress field and other physical fields which were hard to be measured at the mine site. A visual study could be conducted on an expansion form and law of seam combustion goaf under different deposition conditions. The gasification technique model test would not only have the same technique parameters to the site test,could conduct a study on the pollutant precipitation and migration law in the underground coal gasification pro cess and could be applied to the site production. Finally,the development orientation of the model experiment was provided.