<p>The characterization of chemical short-range order (CSRO) in high-entropy alloys (HEAs) as well as its influence on mechanical properties is summarized. As a unique structural feature of HEAs, CSRO is introduced through lattice distortion or strong bonding, reconstructing the local environment at the atomic scale. Experimental studies show that CSRO optimizes the performance of HEAs by regulating dislocation movement, inhibiting deformation twinning, and reconfiguring the lattice strain distribution. Theoretical studies show that CSRO formed a composite microstructure by reducing the system energy and reconstructing the atomic environment, suppressing dislocation movement, and increasing the energy threshold for dislocation nucleation. Additionally, it is of great significance to find the critical point at which the differences in chemical affinity among alloying elements and atomic size differences play a dominant role in the formation of CSRO. CSRO can enhance the strength of HEAs by increasing the shear modulus and unstable stacking fault energy, synergistically optimizing the elastic modulus with interstitial atoms, and triggering unique dislocation pinning mechanisms. In the future, more advanced characterization methods need to be developed, and multi-scale comprehensive research should be carried out to promote the application of CSRO prediction and characterization in the design of HEAs.</p> Graphical abstract <p></p>