Novel hyperbranched polyphenylenes based on both an A(2) + B-3 and an AB(2) + AB approach were synthesised and characterised. Different monomers were prepared and polymerised using a Diels-Alder reaction with sub sequent decarbonylation. The polymer backbones consist of hexaphenylbenzene units which are linked in different positions and functionalised by cyclopentadienone (A) and/ or alkyne groups (B) depending on the monomer ratio. The structure and properties of the resulting polymers were compared to those of hyperbranched polyphenylenes based solely on an AB(2) monomer. All branched products showed high thermal stability and good solubility in common organic solvents such as chloroform or toluene. However, due to steric hindrance, the polyphenylenes produced using the A(2) + B-3 approach exhibited a high percentage of linear units within the polymer structure.