The land rental market is critical for herders to obtain access to land resources. However, in contrast to the numerous studies on the farmland rental market, few studies have focused on the grassland rental market, and analyses of younger herders land renting behaviors from the perspective of social capital are even more rare. This paper addresses three questions: First, what is the current situation regarding younger herders participation? Second, does social capital influence herders renting decisions? Third, is there a difference of herder age on the influence of social capital on grassland renting decisions? Probit model was conducted with data collected from 422 herder households in Inner Mongolia, P.R. China. Findings suggested that 1) Younger herders grassland rental behaviors presented the coexistence of high participation rate and high rental price . 2) An inverse U-shape relationship existed between age and herders land rental decisions; 3) Compared with older herders, social capital played a relatively weak role in promoting the ability of younger herders to rent grassland. Acknowledgement : The authors thank the Foundation of Renmin University of China (16XNI004) for its support and thank colleagues and students from Renmin University of China and Inner Mongolia University for their participation in the field surveys.