The aim of this research is to investigate if the attachment styles significantly predict the decision self-esteem, decision making styles and five-factor personality traits. Subjects of the study were 567 students in total from different faculties of Selcuk University. The results of the study showed that the attachment styles of the students significantly predict decision self-esteem, decision making styles and personality traits. It was seen that secure attachment style is the most significant predictor of decision self-esteem and vigilance, buck-passing, procrastination scores of decision making styles, whereas the most significant predictor of hypervigilance decision making style is fearful attachment style. Secure attachment style is the most significant predictor of neuroticism, extraversion, agreeableness, openness to experience sub-dimensions of personality traits and the most significant predictor of conscientiousness is preoccupied attachment style.