In order to investigate the changes in the dynamic properties of soil structures and foundation soils under a finite number of repetitive loading cycles, compacted soil specimens were subjected to repetitive loads of sine wave pattern by means of a triaxial compression equipment. By this series of tests, it has been verified that the mode of changes in properties of soil subjected to repetitive dynamic loads is to a large extent affected by the moisture content of the soil and also by the amplitude of the load. It has also been found that considerable change of soil properties takes place in the first 10 cycles or so of loading and this change decreases thereafter exponentially.