Abstract:The molting behavior of common lizard (Zootoca vivipara) was observed directly in the laboratory from May to August, 2014. These lizards were transported to our laboratory in Harbin and were housed in the communal cage with moist soil, grasses and pieces of clay tile provided as shelter sites. Food including mealworm larvae (Tenebrio molitor) and house crickets (Achetus domestica) dusted with multivitamins and minerals and water were provided daily. Hatchlings were collected, weighed and measured the same as adults every 15 days. Molting behavior, times and cycle of the lizards were record at 8:00, 10:00, 14:00 and 16:00 in a day, respectively. All statistical analyses were performed with the SPSS 13.0. We used linear regression analysis, correlation analysis, one-way analysis of variance (ANOVA), and LSD test to analyze the corresponding data. Throughout the paper, values are presented as Mean SE, and the significance level is set at α = 0.05. The result shows that the molting times of adult common lizards range from 0 to 3 in their breeding period (from June to July) in this study. The molting times of two sexes are not significant difference and not positively correlated with body length and body weight (Table 1). Different with the neonate, the molt of the most adult lizard is usually complete and everted except a small part (Fig 1a, 1b). Molting times do not differ significantly between males and females of Zootoca vivipara (Fig 2). The molting cycle of the adult lizard is not fixed which lasting for 8 days at least. It is same with the neonate lizard (Fig 3). The molting behavior of the neonate lizard is correlated to its allometry and the lasting time of molting is negative correlation with the molting times (Fig 4). The special way of molting in the common lizard may be associated to the artificial feeding condition, or the original living environment as well as their behavior strategy and other relevant factors.