This study aims to find out the extent of the characteristics of soft soil and the strength of soft soil stabilized with sea sand. And to find out whether soft soil stabilized with sea sand can be used as an alternative to landfill. The results showed that soft soil contained silica (SiO2) as much as 46.37%, sea sand 40.475% (SiO2). The basic characteristics of soft clay soils using the USCS method are classified as CH soil types (inorganic clay with high plasticity), with water content of 143.75% including very soft soil. Sea sand addition of 10%, 15%, 20% and 25% shows an increase in the carrying capacity of the soil. The results showed that the largest percentage of stabilized soil soft CBR values with sea sand was at 20% sea sand by 23.33%, and increased by 79.98% from soft soil unstable stabilized CBR values. Land of soft sand stabilized by sea sand 10%, 15%, 20%, 25%, can be used/ fulfilled as landfill material.