A method for on-site measuring 
permeability coefficient of 
landfill gas adopts a measurement 
system comprising a lower opened 
tube well, a 
gas pressure sensor, a 
gas pressure display recording instrument, an extraction pipeline valve, a 
leachate emptying valve, a 
leachate emptying 
pipe, a gas measuring apparatus and a 
centrifugal fan. The method adopting extraction mode comprises the following step 
tube well internal pressure and extraction flow rate are recorded after the gas is stable; and the 
permeability coefficient of 
landfill gas is obtained after the substitution to a 
stationary model. In the method, not only are the conventional extraction pipeline and equipment in a landfill utilized, but also the defects of easy explosion and high hazards which are caused after air and 
methane are mixed when gas injection mode is adopted are overcome, further the characteristics of landfill covering permeability and 
permeability coefficient difference in horizontal direction and vertical direction of the landfill caused by layered landfilling and compaction are fully considered. Therefore, the method provided by the invention has the advantages of high measurement accuracy, simple 
system, and convenience in operation; in addition, key parameters are provided for the 
pollution control and the recycling of the 
landfill gas, so that the method has a promised application prospect.