This study examines the relationship between the Big Five Personality Traits and job performance, job satisfaction, and the role of Human Resources managers as a moderator between job performance and personality traits. Our findings show that there is a significant and positive correlation between Agreeableness (1% level), Extraversion and Openness (1% level), and job performance. Conscientiousness, on the other hand, is negatively correlated with job performance. The study also finds that Conscientiousness, Extraversion, and Openness are positively and significantly correlated with job satisfaction. The implication is that people with these traits are more likely to be satisfied on the job relative to others. HRM is a moderator for Openness, Conscientious, and Agreeableness indicating the important roles of HRM in influencing personality traits. We recommend that potential employees should be examined on their personality traits to know if they possess the Big Five Personality that is desired by the organizations studied to enhance and improve job performance and promote job satisfaction..