This study was performed to evaluate the effect of the use of additional calcium (Ca) sources on growth, quality, calcium content in fruits, and cell wall components of hydroponically grown tomatoes ($Solanum$ $lycopersicum$). In plants treated with $CaCO_3$ and Ca-gluconate (Ca-glu), plant height was greater than controls and plants treated with $CaCl_2$. Notably, the fresh fruit weight of plants treated with additional Ca treatments tended to be reduced as compared to the fruit of plants used as controls. Ca content was the highest in Ca-glu as $0.39g{cdot}100g^{-1}$ at 53 days after anthesis (DAA), but that of control was $0.3g{cdot}100g^{-1}$ at 53 DAA. The additional Ca-glu treatment enforced calcium content of tomato fruit. The soluble solid content was high in order of $CaCl_2$, control, Ca-glu, and $CaCO_3$. Additional Ca treatments led to an increase in fruit firmness; the firmness was the highest in the Ca-glu treatment as $2.63kg{cdot}12mm^{-1}$ and the lowest in the control as $2.42kg{cdot}12mm^{-1}$. The calcium content in the tomato plants subjected to Ca-glu treatment was the highest and that of control was the lowest. Alcohol insoluble solid (AIS) contents in the control plant was $11.43mg{cdot}g^{-1}$ F.W., whereas in plants treated with additional Ca treatments ranged from 11.54- to $13.14mg{cdot}g^{-1}$ F.W. The lignin contents ranged from 0.07- to $0.10mg{cdot}g^{-1}$ F.W. according to the different additional Ca sources. Cellulose content was the highest in plants treated with Ca-glu and $CaCO_3$, and lowest in the control plants.