Although mind wandering remains ubiquitous in daily life, the processes that underlie and sustain this behavior remain poorly understood. Here, we studied the role of biologically primed temperament traits in moderating the association between mind wandering and the real-life functional outcome of academic success. Ninety-seven participants completed the Mind Wandering Questionnaire, the Adult Temperament Questionnaire, and reported their grade for the highest degree completed or in progress. Individuals with traits of low Effortful control, high Negative affect, and low Extraversion indicated more mind wandering. Effortful control moderated the relationship between mind wandering and academic success, with higher tendency for mind wandering associated with higher academic achievement for individuals with high effortful control, and lower academic achievement for those with low effortful control. These results suggest that the biologically-primed temperament trait of Effortful control represent one of the key mechanisms behind the functional influence of mind wandering on real-life outcomes.