Under repeated seismic loads during an earthquake, increase of pore water pressure in cohesionless, saturated and loose soils leads to decreased shear strength and therefore liquefaction occurs. Literature reports of numerous cases involving damage due to liquefied soil which makes the pile behaviour and performance in liquefied soil even more important. It is possible to investigate the behaviour of piles located in the liquefied soil under inertial loads using linear spring model, p-y method or numerical analyses and a suitable liquefaction constitutive model in time. This study investigates the behaviour of two piles, located in the foundation of the "Niigata Family Courthouse" which was damaged during the Niigata earthquake of 1964, under inertial loads in liquefied soil. The soil profile identified for this case and the piles are analyzed using p-y method and linear spring approach. Pile deformations and bending moments calculated with these two methods were compared.