The concentrated deep seawater, which is highly enriched in not only Na but useful minerals such as Mg, K and Ca is expected to be applicable to the production of high quality tomatoes. In the previous study, we reported that the short term salt stress treatment with the concentrated deep seawater can produce the high sugar tomatoes through osmoregulation in the phloem transport to fruits. In this study, the specificity of fruit quality of tomato grown with the concentrated deep seawater was examined with special reference to antioxidation, amino acid metabolism and sensory properties of fruits under the three different salt stress treatments. Tomato plants (Lycopersicon esculentum Mill.) were grown in hydroponic pots. In each of salt stress treatments, the concentrated deep seawater (DSW) or the surface seawater (SSW) or pure NaCl (NaCl) was applied to the nutrient solution for only two weeks at the stage of rapid fruit growth, where an electric conductivity of the nutrient solution was raised from 1.0 dSm^-1 to 15 dSm^-1. The two weeks salt stress treatment with the concentrated deep seawater brought high quality tomatoes with higher accumulations of sugar, acids, minerals of Mg and K, functional amino acids of γ-aminobutyric acid and proline and with good flavor. Furthermore, the activity of superoxide dismutase in DSW treatment was low as compared with that in SSW treatment and NaCl treatment. However, in this experiment, the significant differences in fruit quality (i.e. growth, contents of sugar, acid and functional amino acids) were not found among the three different salt stress treatments.