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Objective: To correlate the Breeding Soundness Evaluation (BSE) of Charolais and Charbray bulls in the warm sub-humid climate and its effect on the pregnancy rate and calving interval of herds to estimate differences between breeds. Design/Methodology/Approach: BSE was carried out on N = 90 Bulls, Charolais (n = 33) and Charbray (n=57), evaluated in situ during the period of 2017 to 2019. Variables for the bull (age, body condition, libido, and scrotal circumference), semen (concentration, motility, and volume), herd (pregnancy rate and calving interval), and environment (rainy and dry season) were analyzed with the one-way ANOVA, Factorial, Multiple regression and Multivariate analysis. Results: Charolais and Charbray bulls show similar results in the BSE (p>0.05) in a warm sub-humid climate. Study Limitations/Implications: Yearly seasons (rainy or dry) do not affect (p<0.05) the BSE rating. Libido is associated (p<0.05) with age (R= -0.42), sperm motility (R=0.67), sperm concentration (R=0.66) and pregnancy rate (R=0.63). Findings/Conclusions: Variables with high association (p<0.05) with pregnancy rate were libido (R=0.63), motility (R=0.60), sperm concentration (R=0.51) and age (R= -0.50); variables with high association (p<0.05) with calving interval were: age (R=0.74) and libido (R=-0.33). Charolais and Charbray bulls show similar reproductive efficiency in herds under a warm sub-humid climate in Veracruz. [ABSTRACT FROM AUTHOR]