The limited toughness of epoxy resins (EP) significantly hinders their application.While hyperbranched polymers are commonly employed as toughening agents, their poor solubility often leads to drawbacks, including a marked reduction in glass transition temperature (Tg).In this study, a novel hyperbranched poly (aryl ether ketone) resin (pm-HBPAEK-OH) with enhanced solubility was synthesized and evaluated as a toughening agent, for EP.The results indicated that when the content of pm-HBPAEK-OH is 6%, the tensile strength, flexural strength, impact strength, and elongation at break reached 75.1 MPa, 113.8 MPa, 43.5 kJ/m2, and 11.3%, resp., representing enhancements of 10.0%, 13.1%, 112.9%, and 195.0% compared to the pure EP.Addnl., the modified EP exhibited superior thermal stability achieving a Tg of 91.6 °C, which is approx. 15.4 °C higher than that of pure EP, without a significant loss in thermal decomposition temperature