Owing to the biological importance of proteins displayed by spermatozoa and present in seminal plasma (SP) for numerous reproductive processes, major efforts have been undertaken in livestock to identify specific seminal proteins that can be used as potential biomarkers for sperm function after cooling (for liquid storage or cryopreservation) and, ultimately, for fertility. With recent advancements in analytical techniques, research on proteins expressed in either boar sperm or boar SP has substantially increased. Herein, we critically review the relevance of changes in pig sperm and SP proteomes with regards to sperm reproductive biotechnologies and resulting fertility.