The effects of the direct and indirect relationships of personality traits on academic performance are shared in this paper. These complex relationships are examined using Structural Equation Modelling (SEM) with reference to the modified Biggs' 3P model. The major findings of the effects of personality traits on academic performance are (1) the negative effect of a high level of 'agreeableness'; (2) the indirect effects of 'conscientiousness' and 'openness'; and (3) how the effects are mediated through course perceptions. The findings from this study could inform universities on developing more targeted and effective student support and interventions.