Introduction: The assessment of person-environment congruence is important in vocational and career guidance. The aims of this study were to obtain descriptive statistics for the congruence between realistic, investigative, artistic, social, enterprising, and conventional (RIASEC) vocational interests and occupational aspirations, and to relate congruence scores to vocational self-efficacy and the Big Five personality traits in a sample of high school students. Method: The participants were 274 second- and third-year high school students from Cajeme (Sonora, Mexico). The Self-Directed Search (SDS), the Vocational Self-Efficacy Scale and the Global Personality Assessment Scale were administered. Congruence was measured using the Iachan and C indexes. Descriptive statistics and percentile rankings of congruence scores were obtained. To explore the association between variables, partial correlation and hierarchical multiple regression analyses were performed. Results: Female students obtained higher mean scores on the two congruence indexes than male students; however, the difference was only significant for the Iachan index. The Big Five personality traits in the aggregate explained significant amounts of variability in congruence scores, with small to moderate effect sizes. Openness to experience was the only significant predictor. Self-efficacy dimensions were not significantly associated with congruence scores. Discussion or Conclusion: The results provide information in the line of research on the relationships between the congruence construct with the Big Five-factors of personality and vocational self-efficacy. The study has practical implications in vocational assessment and guidance; the descriptive statistics for the two congruence indexes (Iachan and C) will allow more valid interpretations of the scores of this construct in populations with characteristics similar to those of the sample.