Social stigmatization can disrupt the ability of individuals with genetic conditions to successfully adapt to their situation. We offer data on perceptions of stigma from a cross-sectional survey of 174 adults with Marfan syndrome by self-report. Fifty-six respondents (32%) reported feeling discriminated against or socially devalued because of having Marfan syndrome. Endorsement of discrimination was significantly correlated with having depressive symptoms, low self-esteem, the view Marfan syndrome has had significant negative consequences on one's life, striae, and perceptions of workplace discrimination. Nearly 30% of respondents reported withdrawing from social situations that they anticipated would lead to feeling stigmatized, and 25% reported electing to keep their condition secret in potentially stigmatizing situations. Over 50% of respondents reported educating others about Marfan syndrome as a means of coping with their feelings of stigma, and endorsement of education was correlated with viewing involvement in the National Marfan Foundation as important. Instances of workplace discrimination were perceived by 20% of respondents, and 23% reported that they remained in a dissatisfying job due to having Marfan syndrome. Genetics professionals should actively engage patients with Marfan syndrome in discussions about social stigmatization and encourage use of coping strategies aimed at enhancing quality of life.