Samandag Beach is one of the most important nesting habitats of Chelonia mydas (L., 1758), one of the endangered species in the globe. In this study, calcium (Ca), magnesium (Mg) and chromium (Cr) in 135 sand samples collected from the nesting habitat (Samandag) of C. mydas species are examined. Sampling was carried out from three types of sites: (1) adjacent to nest chambers, (2) the adults' tracks, and (3) non-track (one random point from every 2 km) locations. The samples were obtained from three levels at each sampling point; surface (upper layer), medium (30 cm deep) and deep (80 cm) vertically. Some biological data about nesting, activity, such as nest density and nesting success, were also monitored in 2003 nesting season. The mean concentrations of Ca, Me, and Cr in sand are 278 ppm (mg kg(-1)) (+/- 121.97), 317 ppm (+/- 9.92), and 5.40 ppm (+/- 1.38), respectively. Ca and Mg in sand have a significantly positive correlation with nesting success (r = 0.717 for Ca; r = 0.672 for Mg; both p<0.001). Moreover, Cr has a positive correlation (r = 0.760; p<0.001) with nest density. The results indicate that both Ca and Cr concentrations on sand beaches used by green turtles to nest play important roles in their nesting success.