1. A total of 260 individuals of carp was collected from Nakdong and Hyungsan Rivers. 2. The normal dental form of carp is 3, 1, 1-1, 1, 3, but the author observed abnormal dental forms (3, 2 or 1, 1, (+1)-1, 1 or 2, 3). 3. Variation ratios of dental forms are : A. Normal form; 3, 1, 1-1, 1, 3..........88.85% B. Abnormal forms; a. 3, 2, 1-1, 1 or 2, 3..........2.31% b. 3, 1, 1, 1-1, 1 or 2, 3..........5.00% c. 3, 2, 1, 1-1, 1 or 2, 3..........3.07% d. with 2 or 3 bone processes..........0.77% 4. The ratios among the length of first row (I), length of second tooth in first row ($I_{-2}$) and mid line(M) are as follows; 5. The growth of bone process beside second row tooth is not concerned with the body growth. 6. The number of the groove on second tooth in first row increases according to the growth of body.