Gullinbursti (meaning "Gold Mane or Golden Bristles") is a boar in Norse mythology.
When Loki had Sif's hair, Freyr's ship Skíðblaðnir and Odin's spear Gungnir fashioned by the Sons of Ivaldi, he bet his own head with Brokkr that his brother Eitri (Sindri) would not have been able to make items to match the quality of those mentioned above.