Abstract Two novel poly(arylene ether sulfone)s with high biphenylene content (BDS‐PES and BDS‐PDBES) are prepared by nucleophilic substitution polymerization of synthesized 4,4′‐bis(4‐hydroxyphenyl)diphenyl sulfone (BDS) with 4,4′‐sulfonylbis(fluorobenzene) and 4,4‐bis[(4‐chlorophenyl)sulfonyl], respectively. The prepared polymers show high glass transition temperature and excellent high‐temperature mechanical properties. The glass transition temperature of BDS‐PDBES with higher biphenylene content is as high as 300 °C, and BDS‐PDBES can still maintain its 30% storage modulus at 295 °C. In addition, the two novel polymers also show excellent thermal stability ( T d5 = 526 °C), high elongation at break ( ε ≈ 20%), good tensile strength (73 MPa) and modulus (1.73 GPa) and good thermal conductivity ( λ 300°C = 0.28 W ·m −1 ·K −1 ).