Introduction: Education has been regarded as an essential concomitant of all human society and academic achievement is one of the most important goals of education in this competitive age. Mental health and self-efficacy are considered as important variables because they are essential for effective learning. Academic achievement is a complex phenomenon as a dependent variable, is not under the influence of one factor and that is not determined solely by mental health, self-efficacy or any other single variable. The study is covered by the three variables: 'Mental Health', 'Self-Efficacy' and 'Academic Achievement' to explain the nature and scope of the study to a great extent. Hypotheses of the Study: 1. There exists significant relationship between predictor variable Mental Health and criterion variable Academic Achievement among student teachers in Kerala. 2. There exists significant correlation between each of the components of Mental Health and Academic Achievement among student teachers in Kerala. 3. There exists significant relationship between Self-Efficacy and Academic Achievement among student teachers in Kerala. 4. There exists significant difference in Mental Health with respect to: Gender and University. 5. There exists significant difference in Self- Efficacy with respect to: Gender and University. 6. There exists significant difference in Academic Achievement with respect to: Gender and University 7. There exists significant correlation between Mental Health and Academic Achievement when Partialling the effect of Self-Efficacy among student teachers in Kerala. 8. There exists significant correlation between Self-Efficacy and Academic Achievement when Partialling the effect of Mental Health among student teachers in Kerala. 9. There exists significant combined relationship between Self-Efficacy and Mental Health on Academic Achievement among student teachers in Kerala. 10. Each of the associate variables, Mental Health and Self-Efficacy is a significant predictor of Academic Achievement among student teachers in Kerala. Objectives of the Study: 1. To find the relationship between Mental Health and Academic Achievement among student teachers of Kerala. 2. To find the relationship between each of the components of Mental Health and Academic Achievement among student teachers of Kerala 3. To find the relationship between Self-Efficacy and Academic Achievement among student teachers of Kerala. 4. To find whether there exists significant difference in each of the predictor variables Mental Health and Self-Efficacy with respect to Gender and University 5. To find whether there exists significant difference in the criterion variable Academic Achievement with respect to Gender and University 6. To find the correlation between Mental Health and Academic Achievement by Partialling out the effect of Self-Efficacy among student teachers in Kerala 7 .To find the correlation between Self-Efficacy and Academic Achievement by Partialling out the effect of Mental Health among student teachers in Kerala 8. To find the combined relationship of predictor variables, Mental Health and Self-Efficacy on criterion variable Academic Achievement among student teachers in Kerala 9. To test the predictive efficiency of each of the associate variables to predict Academic Achievement among student teachers in Kerala. Methodology in Brief Method adopted: The method used for the present study is survey method. The study is descriptive and co-relational in nature. Sample: The sample for the study consists of 314 students undergoing M.Ed. programme on regular basis in University departments and affiliated colleges in the field of Education under the Universities such as: Kerala, Mahatma Gandhi, Calicut and Kannur in Kerala. Tools used for the study: Data for the study were collected using the following tools: 1. Mental Health Status Scale (M.H.S. Scale)-(prepared and standardized by the investigator). 2. General Self-Efficacy Scale (G.S.E. Scale)-(prepared and standardized by the investigator). Note: The study used the total score of B.Ed. course to assess the academic achievement of the sample selected. Statistical Techniques Used: The relationships of the variable, 'Mental Health' with each of the two other variables viz., 'Self-Efficacy' and 'Academic Achievement' was separately investigated by using the statistical techniques such as :t-Test and ANOVA, Correlation Analysis and Regression Analysis. Major Findings: 1. There is significant relationship between Mental Health and Academic Achievement among student teachers in Kerala. 2. There exists no significant correlation between each of the components of Mental Health such as Attitude toward the Self, Positive Attitude toward Others, Self-Actualization, Autonomy and Perception of Reality with Academic Achievement among student teachers in Kerala. The results indicated that, there exists significant correlation between each of the components of Mental Health such as: Integration, Environmental Mastery and Optimism. 3. There exists no significant relationship between Self-Efficacy and Academic Achievement among student teachers in Kerala. 4. There exists no significant difference in Mental Health with respect to Gender and University. 5. There exists no significant difference in Self-Efficacy with respect to Gender and University. 6. There exists no significant difference in Academic Achievement with respect to Gender. The results indicated that, there exists significant difference in Academic Achievement with respect to University 7. There exists a positive but negligible correlation between Mental Health and Academic Achievement when Partialling out the effect of Self-Efficacy among student teachers in Kerala. 8. There exists a positive but negligible correlation between Self-Efficacy and Academic Achievement when Partialling out the effect of Mental Health among student teachers in Kerala. 9. There exists no significant combined correlation between Self-Efficacy and Mental Health on academic Achievement among student teachers in Kerala for total sample. 10. Each of the associate variables, Mental Health and Self-Efficacy is not significant predictor of Academic Achievement among student teachers in Kerala. Educational Implications of the Study: The present study provides guidelines for families, student teachers, teacher educators, educational researchers, administrators and curriculum makers to looking into the possible way for correlating Mental Health and Self-Efficacy as predictors of Academic Achievement among the student teachers for better educational outcomes as well as for further researches in the research area based on the findings.