In this study, formation process of Ba-ferrite by using molten salt synthesis and its magnetic properties were investigated. Among starting materials, BaC $O_3$was only soluble in the molten salts, but other starting material such as $delta$-FeOOH or F $e_2$ $O_3$was not soluble even at 105$0^{circ}C$. It implies that the dissolved $Ba^{2+}$ diffused on surfaces of F $e_2$ $O_3$(or $delta$-FeOOH), therefore, Ba-ferrtites were formed through surface reaction. However, the magnetic properties of Ba-ferrite prepared by two starting materials (F $e_2$ $O_3$and $delta$-FeOOH) were not different. On the other hand, compared $delta$-FeOOH with F $e_2$ $O_3$m, morphologies and dispersibility of Ba-ferrites prepared by using $delta$-FeOOH were good and Ba-ferrites were obtaioned at lower temperature.