The present study was carried out in order to investigate seasonal variation in tannin, sugar and protein contents of persimmon fruits, Five varieties of Diospyros kaki Thunberg, i. e, Buyoo, Wolha, Kapjubackmok, Pyungmuhek, Heuksi, and Goyom (Diospyros Lotus Linne var. typica Makino) growing in Jeonbug area were used as the experimental material. The result are summarized as follow; 1. Maximum tannin contents were 4% in Buyoo, 5.46% in Wolha, 5.4l% in Kapjubackmok, 5.1 % in Pyunginuhek, 9.2% in Heuksi, and 26.1% in Goyom, respectively. Therefore, Heuksi and Goyom were considered to be the most useful as tannin material. 2. THE most suitable season for tannin extraction was thought to be July with most varieties but it was August with Goyom. 3. The total sugar contents seemed to increse linearly. Linear regressions are as follows. Buyoo ; Y = 0.2394x+3.861 Wolha ; Y = 0.3093x-1.148 Kapjubackmok ; Y = 0.3173x-1.3708 Pyungmuhek ; Y = 0.2796x+0.982 Heuksi ; Y = 0.3233x-3.242 Goyom ; Y = 0.1555x-4.780 4. Average crude protein contents of fruits throughthe year were 5.32% in Buyoo, 4.97% in Kapjubackmok, 4.49% in Goyom, 4.11% inWolha, 4.02% in Heuksi, and 3.6% in Pyungmuhek, respectively. 5. The crude protein contentstend to decrease gradually after fruit setting.