Structurally controlled aggregation course for five porphyrins (etioporphyrin [EP], 5-mono-and 5,lS-di-lp-tolylletioporphyrin [TP and DTP], 5,10,15,20-tetrakislpp-tolyllporphin [TTP], and 5,10,15,2O-tetrakis[3,5-di-tert-b~tylphenyllporphin [TBP]) in dipalmitoyl-phosphatidylcholine liposomes has been monitored by fluorescence and absorption spectroscopy. While TBP shows no tendency to aggregate in liposomes, EP, TP, DTP and TTP form a porphyrin-enriched domain in membrane interior with time. The further aggregation steps within porphyrin clusters resulting in formation of stacked porphyrin aggregates have been observed for EP, TP and DTP.