Significant progress in bio-based epoxy technology development has been achieved in recent years. Many bio-based epoxy resins, bio-based curing agents and additives, and bio-based formulated epoxy materials, as well as their performance, have been investigated. More importantly, certain types of bio-based epoxy resins, bio-based curing agents, and bio-based formulated epoxy products have been commercialized, and their use in actual applications has been realized. Bio-based epoxy technology is developed by using bio-based epoxy materials instead of conventional fossil-derived ones. There are mainly two types of bio-based epoxy resins: conventional epoxy resins and novel epoxy resins, depending on the epoxy resin building-block type used. Bio-based conventional epoxy resins are prepared by using the bio-based epichlorohydrin to replace conventional fossil-based epichlorohydrin. Bio-based novel epoxy resins are usually prepared from epoxidation of renewable precursors such as unsaturated vegetable oils, saccharides, tannins, cardanols, terpenes, rosins, and lignin. Typical bio-based curing agents are bio-based polyamines, polyamides, amidoamines, and cardanol-based phenalkamine-type curing agents. Cardanol is a typical bio-based reactive additive available commercially. Certain types of partially bio-based formulated epoxy products have been developed and supplied for use in bonding, coating, casting, composite, and laminating applications.