［Objective］To integrate hydrophobicity and hardness of long carbon chain modified photocured coatings，a long carbon chain polyurethane-urea acrylate was prepared.［Methods］An intermediate was first prepared by reacting hydroxyethyl acrylate with isophorone diisocyanate，which was then further reacted with bio-based dimeric diamines（Priamine 1074 and Priamine1071） to synthesize polyurethane-urea acrylates（PUUA-1074 and PUUA-1071）. The product structure was confirmed by Fourier transform infrared spectroscopy and ¹H NMR.［Results］The prepared bio-based PUUA coatings exhibited water absorption below 1%，demonstrating excellent hydrophobicity，with no pitting or blistering observed on the PUUA-1074 coating surface after 600 h salt spray testing.Meanwhile，benefiting from the hydrogen bonding reinforcement provided by the urea groups，the PUUA-1074 cured film achieved both good tensile strength（40. 9 MPa）and surface hardness（pencil hardness F）.［Conclusion］ Introduction of urea groups couldimprove the hardness of long carbonchain-modified photocured coatings.