Prediction of male or semen fertility potential remains a persistent challenge that has yet to be fully resolved. This work analyzed several in vitro parameters and proteome of spermatozoa in bulls cataloged as high (HF; n=5) and low field (LF; n=5) fertility after more than a thousand artificial inseminations. Sperm motility was evaluated by Computer-Assisted Sperm Analysis. Sperm viability, mitochondrial membrane potential (MMP), and reactive oxygen species (mROS) of spermatozoa were assessed by flow cytometry. Proteome was evaluated by SWATH-MS procedure. Spermatozoa of HF bulls showed significantly higher total motility than the LF group (41.4% vs. 29.7%). Rates of healthy sperm (live, high MMP, and low mROS) for HF and LF bull groups were 49% and 43%, respectively (p > 0.05). Spermatozoa of HF bulls showed higher presence of differentially abundant proteins (DAPs) related to both energy production (COX7C), mainly OXPHOS pathway, and to the development of structures linked with the motility process (TPPP2, SSMEM1 and SPAG16). Furthermore, we observed that EQTN, together with other DAPs related to the interaction with the oocyte, were overrepresented in HF bull spermatozoa. The biological processes related to protein processing, catabolism, and protein folding were found to be overrepresented in LF bull sperm in which the HSP90AA1 chaperone was identified as the most DAP