Background: Body dysmorphic disorder (BDD) is a common, often undiagnosed, serious condition. The relationship between body dysmorphic disorder and cosmetic surgery is rather complex, as many patients with body dysmorphic disorder search for cosmetic solutions for the imagined defect in appearance. Aims: To assess the prevalence of body dysmorphic disorder and its relationship to the acceptance and use of cosmetic services and body-related variables among Hungarian adults. Methods: Body weight and height, body satisfaction, health state, aesthetic intervention-related experiences, and plans were assessed by a self-report online questionnaire that included the Body Dysmorphic Disorder Questionnaire and the Acceptance of Cosmetic Surgery Scale. Six hundred three subjects (94% women, n = 567, 6% men, n = 36, age M = 40.16 years, SD = 13.32 years) joined the research on a social media platform. Results: The prevalence of BDD is 8.1% (n = 49), 8.1% (n = 46) in women, and 8.3% (n = 3) in men. The BDD-positive group had higher BMI (U = 9641.5, p = 0.028), more plastic surgeries (χ2(1) = 19.682 , p = 0.012), and more acceptance of cosmetic surgery (U = 6664, p < 0.001). The risk of BDD is significantly higher in those who have a lower education (OR = 0.424, p = 0.031), accept cosmetic surgery (OR = 1.031, p = 0.025), plan plastic surgery (OR = 0.351, p = 0.027) and are more dissatisfied with their body (OR = 0.397, p < 0.001). Consideration of cosmetic surgery (U = 7433, p = 0.006) and planning for future plastic surgeries χ2(1) = 7.943, p = 0.019) are more frequent in females. Sixty-six women (11.6%) have already had some intervention, 26.4% plan, and 10.4% probably plan cosmetic surgery, while these data are 11.1%, 8.3% and 5.6% in males. These symptoms occur more frequently among women according to Body Dysmorphic Disorder Questionnaire: avoidance behavior (33.9% vs. 16.7%, χ2(1) = 4.539, p = 0.033), significant mental suffering caused by the perceived flaw(s) (29.8% vs. 13.9%, χ2(1) = 4.178, p = 0.041). The Acceptance of Cosmetic Surgery Scale total score has a significant positive relationship with BDD caseness (β = 0.100, p = 0.011) and the number of blepharoplasties (β = 0.111, p = 0.005) and significant negative relationship with the planning of cosmetic surgery (β = –0.491, p < 0.001). Conclusions: The prevalence of body dysmorphic disorder is high in this non-clinical, unselected Hungarian sample. The risk for body dysmorphic disorder is higher in those interested in cosmetic services; screening for this body image disorder is necessary.