A high-performance triple-crosslinked polymer and a preparation method thereof are provided. The polymer is obtained by curing and cross-linking a monomer having two epoxy groups, a cross-linking monomer and a functional monomer. The polymer contains a cross-linking network formed by covalent bonds and two types of multi-level hydrogen bonds with different strengths. The interaction strength between the covalent bonds and the two types of hydrogen bonds decreases in a gradient. The dilemma of the strength-ductility tradeoff in a high-performance polymer is overcome by forming a triple-crosslinked network with covalent bonds and multi-level hydrogen bonds with different strengths in the polymer. The dynamic and hierarchical hydrogen bonds are broken and recombined timely and continuously to concurrently maintain the complete structure of the polymer network and enable the polymer network to quickly respond to the transmission and dissipation of the external environment.