Purpose: The purpose of our study is to examine the direct and mediating effects of attention-deficit hyperactivity disorder (ADHD) symptoms and urgency, lack of premeditation, lack of perseverance and sensation seeking (UPPS) impulsivity traits on entrepreneurial self-efficacy and entrepreneurial intention as well as to test the moderation impact of ADHD symptoms in the link between entrepreneurial self-efficacy and start-up intention. Design/methodology/approach: The stratified random sampling was approached to recruit the data from 2,566 university students in Vietnam. Cronbach's alpha and confirmatory factor analysis were used to test the reliability and validity of scales. Then, Pearson correlation analysis was utilized to test direct effects, while PROCESS macro was approached to test moderation and mediation impacts. Findings: The study found evidence that ADHD symptoms, sensation seeking, lack of premeditation and lack of perseverance are significantly and directly conducive to the formation of entrepreneurial intention. Yet, ADHD symptoms might weaken the link between entrepreneurial self-efficacy and entrepreneurial intention. Entrepreneurial self-efficacy was also found to partially mediate the link between sensation seeking, lack of premeditation, and lack of perseverance and intention to become an entrepreneur. Practical implications: The findings provide constructive recommendations for policymakers and educators to nurture and foster university students' entrepreneurial activities as well as to restrain the negative effects of ADHD symptoms on youths. Social implications: Understanding the impacts of psychiatric symptoms, such as ADHD and UPPS impulsivity, on entrepreneurial activities provide useful insights to individuals with ADHD symptoms, the community and the society to restrain the detrimental impacts of psychological disorder symptoms and consider entrepreneurship as a career choice. Originality/value: The study is expected to have a significant contribution to psychological entrepreneurship literature by broadening our horizons of the links between psychiatric symptoms and entrepreneurial intentions. Especially, this study reveals that ADHD symptoms and UPPS impulsive traits are significantly correlated with intention to become entrepreneurs and the link between entrepreneurial self-efficacy and entrepreneurial intention become weaker when the degree of ADHD symptoms is high.