Risk perception has been an important construct in understanding tourists’ trip planning. Surprisingly, while tourists’ perceived tourist–host identity risk (THIR) plays an essential role in this process, its effects have been overlooked. Against this backdrop, this study develops a THIR scale and investigates how it shapes the intention of mainland Chinese tourists to revisit Hong Kong, and also investigates the spread of positive word-of-mouth (WoM) by conducting multiple online surveys with mainlanders. The results show that THIR is a uni-dimensional construct which is robustly measured by 12 items. It undermines revisit intention and the spread of positive WoM because of lower emotional solidarity followed by anticipation of unpleasant experience. This negative serial mediation is weaker for people who have a strong Chinese identity and perceive high THIR of an alternative destination (Macao). Meaningful implications are provided for destination marketers.