Electrochemical and thin-layer spectroelectrochemical properties of mono- and bis-porphyrins containing a β,β′-fused tetraazaanthracene (TA) group were examined in CH₂Cl₂, PhCN and pyridine containing 0.1 M tetra-n-butylammonium perchlorate as supporting electrolyte. The investigated mono-porphyrins are represented as (PTA)M, where M = 2H, Cu(II) or Zn(II) and PTA = the dianion of 5,10,15,20-tetrakis-(3,5-di-tert-butylphenyl)-6′,7′-dimethyl-1′,4′,5′,8′-tetraazaanthraceno-[2′,3′b]-porphyrin, while the bis-porphyrins are represented by M(P)-TA-(P)M, where M is H₂, Cu(II) , Zn(II) , Ni(II) or Pd(II) and P is the dianion of 5,10,15,20-tetrakis-(3,5-di-tert-butylphenyl)porphyrin. The effect of the fused TA group on the redox potentials and UV-visible spectra of the neutral, electroreduced and electrooxidized porphyrins is discussed and the data compared to what is observed for related mono- and bis-quinoxalinoporphyrins of the type (PQ)M and (QPQ)M, where Q is a β,β′-fused quinoxaline group. Each TA-linked bis-porphyrin exhibits a strong interaction between the two equivalent porphyrin macrocycles, the magnitude of which is dependent upon the specific metal ion.