The aim of the present study was to predict subjective well-being based on cognitive emotion regulation strategies, defensive styles, honesty and psychological needs. In terms of objective, it is a fundamental research, and data collection, it is a correlation research. For this purpose, 289 students were selected using random sampling from students of the Bu-Ali Sina University of Hamadan in the academic year 2015-2016. The participants were asked to complete Subjective Well-Being Scales, Cognitive Emotion Regulation Questionnaire, Honesty Scale, Defensive Styles Questionnaire and the Psychological Needs Questionnaire. Data were analyzed by the analysis of variance and stepwise regression. The results showed that there were positive and significant relationships between the variables of honesty, positive reappraisal strategy, relationship, autonomy, and defensive style with mental well-being, and the non-developed styles of defense had a negative but non-significant relationship with mental well-being. These variables (honesty, positive strategies of cognitive emotion regulation and mature defensive style were able to predict 15% of the total variance of Subjective Well-Being. The subjective well-being has positive effects on physical and psychological health of people. Thus, the findings of this study have practical implications in the clinical areas.