In this paper decision-making styles, locus of control, and average grades in exams are examined as correlates of procrastination in a sample of 185 university students (mainly female students) recruited from mandatory courses for degrees in psychology and pedagogy at the University of Catania (Italy). Method: We used the Decisional Procrastination Scale (Ferrari, Johnson, & McCown, 1995), consisting of five Likert-type items useful for analyzing the procrastination; the Decision-Making Styles (Di Nuovo & Magnano, 2013), chosen for measuring the doubtfulness, delay, proxy, and no problem styles with 15 Likert-type items; the Locus of Control of Behavior Scale (Craig, Franklin, & Andrews, 1984) used to evaluate internal and external loci of control. The data were gathered through an online anonymous questionnaire and were analyzed using the multiple linear regression model to assess how styles of decision-making, locus of control, and average grades in exams affect the decision to procrastinate in university students. The main findings of this study indicate that doubtfulness and delay decision-making styles correlate with high decisional procrastination together with low average grades at university exams. Locus of control is excluded by the proposed model. Conclusions: These findings suggest pursuing a deeper investigation of the various types of procrastination and the measures used for analyzing the academic achievement in university students.