A numerical model (SK-EST) for estimating hydraulic conductivity using monitoring data of underground LPG storage cavern was developed. The model calculates hydraulic conductivity from matrix equation which is established from the distribution of hydraulic potential. To verify the applicability of this model, an inverse analysis was performed using the monitoring data of pressure cell of an operating underground LPG storage cavern. And also using the water pressure parker test data which were obtained to look over the operation capability of pressure cell, conductivity variation with depth was estimated using the developed numerical model (SK-EST) and was compared with in situ results.