Abstract:In order to understand factors influencing the development of laterality in maternal cradling behavior and neonate nipple preference of Qinling golden monkeys (Rhinopithecus roxellana), we collected behavioral data using scan sampling from 32 newborn infant - mother pairs. We collected 3 675 samples of neonate nipple preference and 3 661 samples of maternal cradling laterality. We calculated a lateral bias index (LBI) by subtracting the number of left-sided observations (L) from the number of right-sided observations (R)and dividing by the total number of observations,i. e. (R - L / (R +L). We found a left-side group-level preference of maternal cradling in primiparous females (t(6) = - 3. 890,P =0. 008), and a significant left-side nipple group-level preference in infants who were born to primiparous females (t(6) =- 3. 731,P = 0. 010). We found no group-level preference direction among multiparous females,(neonate nipple preference: t(24) = 0. 854,P = 0. 402; maternal cradling laterality: t(24) = 1. 955,P = 0. 062). Moreover,most (8 of 9) females differed in their direction of maternal cradling laterality among successive procreating periods (N1 =8, N2 = 1, P =0. 039). Our results suggest that experience may affect neonate nipple preference and thus affect maternal cradling laterality in this species.