A conjugated-bisimidazolylporphyrin bridged by bis(ethynylfluorene) was synthesized and organized into linear polymer through self-coordination having mean molecular weights, M-w and M-n, of similar to 2.1 x 10(5) Da and similar to 1.6 x 10(5) Da, respectively. A large two-photon absorption cross section value of 3.4 x 10(5) GM (per dimer unit) was observed. This value was comparable to that of the previously reported self-assembled linear polymer consisting of butadiyne-bridged imidazolylporphyrins. The two-photon absorption properties could be controlled by tuning the wavelength and absorption intensity of the one-photon absorption.