Pile foundations are the most popular form of deep foundations used for both onshore and offshore structures. They are often used to transfer large loads from the superstructure into deeper, competent soil layers particularly when the structure is to be located on shallow, weak soil layers. Bored piles are commonly used to support heavily loaded structures such as high rise buildings and bridges in view of its low noise, low vibration and flexibility of sizes to suit different loading conditions and subsoil conditions. Many techniques have been proposed to improve the pile capacity. This paper discuses a new technique for increasing the pile capacity by using swelling concrete. Experimental testing program was carried out to investigate the influence of pile length (Le), pile diameter (D), water cement ratio (w/c), and relative density of soil (Dr) on the capacity of bored piles when using swelling concrete. This paper summarizes the effect of increasing skin-friction resistance on the capacity of bored pile by using swelling concrete that causes increasing in the volume of concrete mass. The main conclusions of this study is increasing the ultimate capacity of pile by swelling concrete (α)% from 10.4% to 30.4%.This study concluded to an empirical equation relating between different studied parameters which affect the ultimate capacity of bored piles with the use of swelling cement.