The ability of α-CD, β-CD and γ-CD to break the aggregates in the solution of the title porphyrin (TPPS 4 ) and to form inclusion self-assemblies has been studied by UV/Vis and 1 H-NMR (ROESY). The behaviour of TPPS 4 in the presence of α-CD, β-CD and γ-CD has been compared to that of sodium p-toluenesulfonate and sodium benzenesulfonate. TPPS 4 in neutral media forms inclusion assemblies, through its meso-phenyl groups, with β-CD and γ-CD, but not with α-CD. Diprotonated TPPS 4 , which has a different geometry from the free base, forms an inclusion assembly only with β-CD. The inclusion assemblies of TPPS 4 with β-CD and γ-CD show different geometry: introduction of the phenyl substituent through the cyclodextrin secondary face for β-CD and through the primary face for γ-CD. © 1995.