Abstract： As a critical stage of consumer behavior, product disposition is closely related to the development of secondhand markets, ecology and public welfare. It is thus vital to examine the antecedents of product disposition behavior. Based on identity signaling perspective, we proposed a positive effect of “dress same” (i.e., incidental similarity of identity-signalling vs. non-identity-signaling products) on consumers’ product disposition intentions, with embarrassment as the underlying mechanism. Meanwhile, this paper also examined the moderating role of comparison of physical attractiveness in the aforementioned effect. Four studies were conducted to test our hypotheses. Study 1 was designed to test the main effect of “dress same”. Participants were randomly assigned to two conditions (i.e., incidental similarity of jacket vs. cellphone case). They were first instructed to read and imagine a scenario where they incidentally found a classmate wearing the same jacket (vs. using the same cellphone case) as theirs when they entered the classroom. Afterwards, they indicated their intentions to dispose of that jacket (vs. cellphone case). Study 2 was conducted on MTurk to test the mediating role of embarrassment and to preclude other alternative explanations. Similarly, participants read and imagined that they incidentally found a coworker wearing the same jacket (vs. riding the same bike) as theirs in a social interaction. Moods and product disposition intentions were measured subsequently. In study 3, we employed three product stimuli of the same product category (outfit: jacket vs. jeans vs. sports shoes) to rule out the confounding effect induced by product attributes and to enhance the robustness of our results. Study 4 further examined the moderating role of comparison of physical attractiveness using a 2 (incidental similarity of T-shirt vs. umbrella) * 2 (direction of comparison: upward vs. downward) between-subjects design. Comparison of physical attractiveness was manipulated by instructing participants to imagine that their physical attractiveness is superior or inferior to the person depicted in the scenario. In line with our predictions, “dress same” had a significant positive effect on consumers’ product disposition intentions, driven by feeling embarrassed. This effect was robust by using both student and non-student samples and independent of product visibility, price, and endowment effect. Moreover, our results also revealed a significant moderating role of comparison of physical attractiveness in the aforementioned effect. In the upward comparison condition, the main effect of “dress same” on product disposition intentions as well as the mediating effect of embarrassment was enhanced, but they were attenuated in the downward comparison condition. Our findings contribute to the literature in several different areas. First, by examining how “dress same” influences consumers’ product disposition intentions, this research enriches the literature of product disposition behavior in particular and consumer decisions in general. Second, our findings shed light on the literature of incidental similarity by exploring its negative consequences. Third, the current research contributes to the embarrassment literature by examining embarrassment in an important consumption context (i.e. “dress same”). Finally, we also extend the application of social comparison theory in consumer behavior research.