We examined the association of self‐reported and teacher‐rated student characteristics assessed at the end of primary school with all‐cause mortality assessed through age 52. Data stem from a representative sample of students from Luxembourg assessed in 1968 (N = 2,543; M = 11.9 years, SD = 0.6; 49.9% female; N = 166 participants died). Results from logistic regression analyses showed that the self‐reported responsible student scale (OR = .81; CI = [.70; .95]) and the teacher rating of studiousness (OR = .80; CI = [.67; .96]) were predictive for all‐cause mortality even after controlling for IQ, parental SES, and sex. These findings indicate that both observer–rated and self–reported student behaviors are important life‐course predictors for mortality and are perhaps more important than childhood IQ.