Background: Intrapersonal and interpersonal Emotional Competence (EC) predicts better health and disease adjustment. This study aimed to validate a short version of the Profile of Emotional Competence (PEC) scale for cancer patients. Methods: Five hundred and thirty-five patients with cancer completed a self-reported questionnaire assessing their intra- and interpersonal EC (PEC), their anxiety and depression symptoms (HADS), and their health-related quality of life (QLQ-C30). Confirmatory factor analyses and Item Response Theory models with the Partial Credit Model were performed to validate and reduce the scale. Findings: The Short-PEC (13 items), composed of 2 sub-scores of intra- (6 items) and interpersonal (7 items) EC, showed an improved factorial structure (Root Mean Square Error of Approximation (RMSEA) = 0.075 (90% confidence interval 0.066-0.085), comparative fit index = 0.915) with good psychometric properties. Discussion: Future studies should use the Short-PEC to explain and predict the adjustment of cancer patients. The short-PEC could be also used in clinical routine to assess the level of EC of patients and to adapt psychosocial intervention.