Nerve growth factor-β (NGF) is a seminal plasma protein in bulls, and its expression on sperm head has been demonstrated to be positively and strongly correlated with sire conception rates (SCR). Although this correlation was speculated to be due to NGF effects on sperm motility, recent studies suggest that NGF in seminal plasma may play a beneficial role on conceptus development following insemination and may regulate the function of the bovine oviducts via its interactions with gonadotrophins. The objective of this study was to determine if seminal plasma NGF concentrations differed based on SCR deviations. Our hypothesis was that bulls with positive SCR deviations would have higher seminal plasma NGF concentrations than those with 0 or negative deviations. Semen aliquots (200 µL) were obtained from Holstein (n = 53) and Jersey (n = 7) bulls collected by artificial vagina during routine semen collection at a commercial stud operation (Select Sires, Inc., Plain City, OH). Individual samples were frozen at −80°C until processing. The SCR scores were provided for each bull by Select Sires. Bulls were allocated to 2 categories: (1) negative/0 SCR deviations (NEG); or (2) positive SCR deviations (POS). Upon thawing, samples were centrifuged at 12,000 × g for 10 min to harvest seminal plasma. Concentrations of NGF were measured using an enzyme-linked immunoassay (ELISA Duoset, #DY256; R&D Systems Inc.). Samples were processed and measured in duplicate according to the manufacturer instructions. Statistical analyses were performed using a Welch 2-sample t-test in R version 3.2.2. Intra-assay CV was measured to be ~7%. Bulls in the NEG category had lower seminal plasma NGF concentrations (4.1 ± 0.5 µg/mL) than those in the POS category (5.3 ± 0.4 µg/mL; P = 0.05). These results suggest that seminal plasma concentrations of NGF in bulls are associated with sire fertility deviations. Future studies are needed to determine if this is a causative relationship and whether adding NGF to semen extender could enhance semen freezing ability and AI conception rates in cattle.