This experiment was conducted to investigate the effects of temperature and time of sedimentation and dilutor on the a, pp.arance of B-body in top and bottom fractions at separation of X and Y- chromosome bearing spermatozoa in boar semen. 1. The top fraction showed higher a, pp.arence rate of B-body than the bottom. 2. Sixty minutes at 5 and 15$^{circ}C$ and 90 min, at 25$^{circ}C$ showed highest difference of B-body a, pp.arence rate between top and bottom fractions. The highest difference was shown in the treatments of Sg at 5$^{circ}C$, C at 15$^{circ}C$ and P at 25$^{circ}C$. 3. The highest difference was shown in the treatments of 25$^{circ}C$ and Sg for 30 min, 15$^{circ}C$ and P for 60 min. and 25$^{circ}C$ and P for 90 min. 4. Sixty minutes in C, P, S and Sg dilutors showed the highest difference. 5. 25$^{circ}C$ of the temperature levels, 60 min of the time levels and P of the dilutor levels showed the highest difference. 6. The difference was given due to the individual boar.