The study was done in Tien Yen Bay of Quang Ninh province (Northeast Vietnam) to examine the spatial distribution of 13 trace elements, including Ni, Co, V, Cd, Cu, Mn, Mo, Cr, Pb, Zn, As, Hg, Sb in surface sediments of the. Bay, in order to understand the mechanisms of trace element concentrations and to assess sediment quality. The results show that the surface sedimenis were composed of sandy mud, muddy sand, and sand The trace elements were highly concentrated in sediments close to river mouths and were decreased seaward and southeasternward of the bay. The trace elements positively correlated with each oiher. The trace element concentrations were controlled by the TOC content and the fine sediment grain size (0,063 mm). According to the Canadian ISQGs, Geoaccumulation index, and pollution load index, the surface sediments were contaminated by trace elements (As, Hg, Sb, Cu, Pb, Zn, Cd, Cr, Mo).