Hospitalizations for heart failure among young adults and middle-aged individuals have increased. The aims of the present study were to evaluate the association between birth weight and risk of adult heart failure and the importance of change from low birth weight to overweight/obesity at young adulthood. We used the population-based body mass index (BMI) Epidemiology Study cohort Gothenburg (n = 35 659) with birth weight and young adult BMI (20 years) available from child healthcare records, school health records, and military conscription register for men born 1945-1961. The cohort includes all children who finished school, which was mandatory, in Gothenburg, Sweden. Information on heart failure diagnosis was retrieved from the National Patient Register and the Cause of Death Register (n = 415). In cox regression analyses, there was an inverse association between birth weight and risk of heart failure [hazard ratio (HR) 0.83 per standard deviation (SD), 95% confidence interval (CI) 0.76-0.90], and a direct association for young adult BMI (HR 1.48 per SD, 95% CI 1.36-1.61). Of note, individuals with birth weight in the lowest tertile, who were overweight/obese in young adulthood had a five-fold risk of heart failure (HR 4.95, 95% CI 3.36-7.31) compared with individuals in the middle birth weight tertile who were normal weight at 20 years. Birth weight was inversely associated with the risk of hospitalization due to heart failure. The combination of low birth weight and overweight/obesity in young adulthood results in excess risk of heart failure beyond that of low birth weight or young adult overweight/obesity separately. These findings indicate the need of a life course perspective in heart failure prevention and risk assessment.