To reduce the free hydroxyl groups of card-bisphenol (CBP) based polybenzoxazine matrix (CBPA-PBz), hybridized with various cross-linkers, such as anhydride and dicarboxylic acid through esterification by in-situ polymerization. The CBP was synthesized using cardanol and benzaldehyde as per our earlier report, then it was converted into benzoxazine (CBPA-Bz) monomer using aniline and paraformaldehyde through Mannich condensation. The CBPA-Bz was formulated with equal mole ratios of six different cross-linkers (CLs), and it was polymerized at high temperature. This offers a highly cross-linked polybenzoxazine network along with the skeleton of CLs via the formation of ester linkages with free hydroxyl groups generated by the benzoxazine unit during the curing process. All six CBPA-CL-PBz matrices possess superhydrophobic (WCA ≥150°) and good anticorrosion behaviors particularly the CBPA-DSA-PBz, which exhibits above 99 % corrosion inhibition efficiency towards the protection of mild steel surfaces.