We assessed perceptions of recently proposed UK obesity policies (mandatory calorie labeling, banning of advertisements of unhealthy food and drinks online and before 9 pm on TV, and banning "buy one get one free" deals for unhealthy food and drinks) in people with an eating disorder (ED) and other mental health conditions. A total of 1273 participants with a self-reported lifetime mental health condition (N = 583 with an ED) completed an online survey in September-November 2022. Multinomial logistic regression was used to examine support for and potential adverse effects of policies in participants with and without an ED. A qualitative analysis of the potential effects of the policy on current ED symptoms was also conducted to better understand how and why policies may be damaging or beneficial. Participants with an ED had a lower level of support for the implementation of the calorie labeling policy compared to those without an ED (43% vs. 58%). Half of the participants with an ED (55%) reported that labeling may worsen their ED symptoms. Qualitative data indicated perceived potential harm (e.g., a gateway to relapse, negative effects on mood) and perceived benefits (e.g., feeling informed and reassured) of calorie labeling in participants with an ED. No differences in support or perceived harms of the other two policies were observed between participants with versus without an ED. Future studies are warranted to explore the potential effects of calorie labeling and how to mitigate negative impacts on people with an ED. This research is the first to assess the perceptions of UK obesity-related policies in people with an ED and other mental health conditions. Participants with an ED (vs. without) were more likely to disagree with the government implementing the calorie labeling policy. These findings highlight the potentially harmful effects of calorie labeling in people with an ED and the need for future research to understand how to mitigate negative impacts.