Octaethylporphyrin-dihexylbithiophene-dimethylaniline triads were synthesized. The triads showed color change from green to yellow upon addition of trifluoroacetic acid. VT-NMR and UV-vis measurements revealed acid- and heat-driven multistimuli-response behaviors. In comparison with pyridine-connected analogs, a porphyrin-bithiophene diad moiety connected with diacetylene linkage expands the difference in basicity between dimethylaniline and pyridine.