The purpose of this study was to document the development of head circumferences, changes of the eyes, and the time of eruption of deciduous teeth in Shih-tzu dogs. In 12 pups of 4 Shih-tzu bitches, the development of head circumferences were estimated from whelping day (Day 0) to 41 days after birth, and the changes of the eyes and the time of eruption of deciduous teeth were estimated from whelping day to 45 days. The head circumferences were 11.24±0.67 (mean±SD) cm in Day 0 and 19.87±1.42 cm in Day 41 and the daily increased length was 0.22±0.08 cm, respectively. The changes of the eyes were determined the first and the completely opening time of eyes. The first and completely opening time of the eyes in pups Day 10.75±0.97 (range: 9.50~13.00) and Day 13.17±1.27 (11.50~15.33), respectively. In the time of deciduous teeth eruption in Shih-tzu, the first day of eruption was started in Day 35.90. The rank of deciduous teeth eruption was C1, C1, P3 I3, I2, P4, I1 and P2, respectively.