This study explores the effects of two affective factors, reading anxiety and learning motivation on incidental vocabulary acquisition (IVA) under Chinese context. Fifty-two sophomores form a comprehensive university in southern China were enrolled in this study; data were collected through questionnaires, IVA test, and semi-structured interviews. This study identified the signifi- cant relationship between IVA and learning motivation but reading anxiety was non-significant. The findings contributed empirical evidence to the effects of affective factors on Chinese students'incidental vocabulary acquisition.