Study of loading rate effect on behavior of clay under one-way undrained cyclic loading was conducted by using triaxial automated system apparatus under stress controlled and undrained condition. The rests were carried out on Depok clay samples which compacted rising Standard Proctor at loading rate of 0, 05 and 0,5 %/min. and with a confining pressure (o3) of 50 kPa on sample. The samples were saturated until the coefficient B higher than 0.97. The test results indicated that the larger of delta-strain occured or higher loading rate.