Objective: Despite the transdiagnostic importance of emotional dysregulation in psychopathology, the exact nature of emotional dysregulation in somatic symptom disorders (SSDs) is still unclear. The present study compared measures of emotional reactivity, emotion regulation (ER), and regulatory choice between n = 62 individuals with SSD ( Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition ) and n = 61 healthy participants., Methods: Participants underwent two ER tasks, assessing a) efficacy of reappraisal and suppression, and 2) regulatory choice, while electrodermal activity and heart rate variability were recorded. In addition, self-reports (Emotion Reactivity Scale, Emotion Regulation Questionnaire, Difficulties in Emotion Regulation Scale) regarding habitual emotional reactions and regulation strategies were assessed., Results: Individuals with SSD reported significantly higher trait emotional reactivity (Emotion Reactivity Scale; p < .001, d = 1.61), significantly more trait ER difficulties (Difficulties in Emotion Regulation Scale; p < .001, d = 1.62), and significantly lower reappraisal use in daily life (Emotion Regulation Questionnaire; p < .001, d = -0.75). On a behavioral and physiological levels, no significant group differences were found regarding emotional reactivity (subjective ratings of emotional stimuli in task 1, p values = .653-.667; electrodermal activity: p values = .224-.837), ER (task 1: p values = .077-.731; heart rate variability: p values = .522-.832), or regulatory choice (task 2: p = .380). Although individuals with SSD were equally effective in state ER (task 1), they perceived ER during the task as significantly more effortful ( p = .038, d = -0.38)., Conclusions: Results suggest that dysregulated emotions might not result from lacking abilities in implementing ER effectively, but rather could arise from less frequent ER initiation because ER is perceived as more effortful., (Copyright © 2022 by the American Psychosomatic Society.)