Abstarct: The chemical compounds in the sediments which are in contact with water, are of important effective parameters in the water quality. The present research was conducted to investigate the water resources pollution in southeast of Tabaxsein Plain as well as the medical geology of the region. The ICP-MS techniques were employed to analyze 4 rock samples as well as 16 sediment samples. In addition, 18 water samples including 11 samples from the wells, 3 samples from the qanats, 3 samples from the river, and 1 samples from a spring were collected in order measure the concentrations of anions and cations while the concentrations of elements were determined through ICP-MS techniques. baxsed on the environmentally importance of the elements and their concentration, Si, Sr, Br, B, F, Zn, V, S, P, Ni, Mg, Fe, Cu, Cr, As, and Al were selected for further investigations. Geological studies showed that the rocks in the region are mostly ultramafic igneous rocks, basaltic- andesite flow, and sedimentary rocks such as marl, shale, and evaporative minerals. The geochemical studies showed that the concentrations of arsenic, cupper, iron, and vanadium in the sample of sediment from basaltic- andesite flow rocks was higher than in the other sediment samples. Also, chromium, nickel, and magnesium have much higher concentrations in the sample of sediment from ultramafic rocks comparing with other sediment samples while abandon of most other elements in these samples were detected. In terms of the modified contamination degree, the samples of sediment from ultramafic rocks were the highest. Enrichment factor, geoaccumulation index, and contamination factor were indications of relatively high contamination by chromium and nickel in the sample of sediment from ultramafic rocks. According to the results of correlation matrix, cluster analysis, and main component analysis, the above elements can be classified into three groups: 1- Cr, Ni, and Mg; 2- Sr, P, and F; and 3- V, Fe, Al, and Zn. The results of chemical analyses of water samples showed that the concentrations of sulfate, chloride, sodium, magnesium, bromium, and strontium and total hardness, total dissolved solids, and EC in the water samples from the vicinity of the old lake perimeter, located on the east of the basin, were higher than the other water resources. Also, the concentration of chromium in the water samples from the vicinity of ophiolite belt in the west of the basin was higher than the other samples. The distribution of the concentrations of elements and the heavy mextals in the water resources of the study area indicated that the concentrations of Cu, V, Si, and F in the upstream qanat which is in the direct contact with the sediments from basaltic- andesite flow were higher than in the other samples. The concentration of fluoride in all water resources of the region, including drinking water resource (Q1), was higher than allowable values by Iranian Standard guideline 1053. A statistical investigation was conducted on the people aged 7 to 16 years which showed that dental fluorosis is very common between the residents in the region in a way 65% of the 3-16 year old people were diagnosed with fluorosis degree of 3 or above. The study also indicated that the degree of the dental fluorosis increases with age and more prevalent in males.