Previous findings on the relationship between procrastination and academic performance are inconsistent. We conducted a meta-analysis of 33 relevant studies involving a total of 38,529 participants to synthesize these findings. This analysis revealed that procrastination was negatively correlated with academic performance; this relationship was influenced by the choice of measures or indicators. The use of self-report scales interfered with detection of a significant relationship between procrastination and academic performance. The demographic characteristics of participants in individual studies also affected the observed relationship. Implications of this meta-analysis are discussed.