Introduction: This research aims to analyse how optimism, self-esteem and social support help to predict academic stress. Method: The sample consisted of 123 students aged 20 to 31 years old, from the 3rd Year in the Psychology Degree. Students completed the Rosenberg Self-esteem Scale, the Life Orientation Optimism Questionnaire (LOT-R), the Frequency and Satisfaction with Social Support Questionnaire and the Student Stress Inventory-Stress Manifestation (SSI-SM). Three linear regression analyses were conducted, each on a different variable: manifestations of physiological, behavioral and emotional stress. The predictor variables were: optimism, pessimism, self-esteem and frequency and satisfaction with social (emotional, instrumental and informational) support. Results: Results showed that the physiological manifestations of stress are not predicted by the used predictor variables, while there is significant proof that the behavioral manifestations of stress are predicted by satisfaction with instrumental social support and optimism. There is significant proof that the emotional manifestations of stress are predicted by optimism and pessimism. As for self-esteem, it did not prove to be significant. Finally, a MANOVA analysis was conducted, showing the main effects to be optimism, satisfaction with instrumental support, age and gender. Discussion: The hypotheses of the study have been partially met.