IMPORTANCE Transparency of industry payments to physicians could engender greater public trust in physicians but might also lead to greater mistrust of physicians and the medical profession, adversely affecting the patient-physician relationship. OBJECTIVE To examine the association between nationwide public disclosure of industry payments and Americans' trust in their physicians and trust in the medical profession. DESIGN, SETTING, AND PARTICIPANTS Survey study using difference-indifference analyses of a national longitudinal survey comparing changes in states where industry payments were newly disclosed by Open Payments with changes in states where payments information was already available because of state sunshine laws. The US population-based surveys were conducted in September 2014-shortly before the initial public disclosure of industry payments-and again in September 2016. Final analyses were conducted September through December 2018. Participants were adults 18 years and older (n = 1388). EXPOSURES National public disclosure through Open Payments of payments made by pharmaceutical and medical device firms to physicians. MAIN OUTCOMES AND MEASURES Wake Forest measure of trust in one's own physician and Wake Forest measure of trust in the medical profession. RESULTS Of the 3542 original survey respondents, 2180 (61.5%) completed the second survey 2 years later, and 1388 named the same most frequently seen physician in both surveys. The mean age of respondents at the time of the first survey was 53 years, and 749 (54.0%) were women. Race/ ethnicity was white in 76.6% (1063 of 1388) and non-Hispanic black in 8.0% (111 of 1388). Public disclosure of payments was associated with lower trust in one's own physician regardless of whether respondents knew their physicians had received payments (decrease in Wake Forest measure of trust in one's own physician of 0.56 point; 95% CI, −0.79 to −0.32 point; P < .001). Open Payments was also associated with lower trust in the medical profession (decrease in Wake Forest measure of trust in the medical profession of 0.35 point; 95% CI, −0.58 to −0.12 point; P = .004). CONCLUSIONS AND RELEVANCE Nationwide public disclosure of industry payments may be associated with decreased trust in physicians and in the medical profession. More judicious presentation of payments information may counteract unintended negative trust and spillover consequences of public disclosure.