We examine whether the sustainable character of an investment impacts asset prices. We use experimental markets with the structure introduced by Smith, Suchanek, and Williams (1988) to investigate the impact of sustainable attributes. Prior studies suggest that investors experience positive emotions when choosing a sustainable investment and that positive emotions correlate with purchases and overpricing. The objective of our study is to investigate the implied relationship in a controlled lab environment. Specifically, we test whether sustainability positively influences asset prices through its positive impact on emotions. We manipulate sustainability levels by providing different sustainability information about the tradeable asset and analyze investors’ emotions during trading using a face-reading software. Moreover, we test how participants’ sustainability preferences affect their trading behavior.