Since the outbreaks of huge earthquakes in Taiwan and Turkey in 1999, attention has been paid to surface fault rupturing causing damages to various civil engineering structures. The mechanism of surface fault rupturing is significantly affected by characteristics of fault movement and unconsolidated surface layer, and very little has been elucidated for the cases of strike-slip faults and oblique faults. This study examines a series of model tests of strike-slip faulting using sand. Characteristic features of shear band structures observed on the surface of model sand layer are investigated.