In coalfield exploration in Runan County of Henan Province,thickness of tertiary and quaternary formation is up to 700 m,water sensitive clay,sandy clay,sandy argillite,aleurolite and gravel strata are often encountered.These easily cause hole diameter's shortage or enlargement,wall of hole collapsing and breaking.According to the strata feature,LG plant glue mud was chosen to solve these difficult problems.It is proved by application that LG mud obviously controls hole diameter's shortage or enlargement,wall of hole collapsing and breaking,greatly reduces borehole accident with drilling efficiency risen.