A microporous bithiophene polymer (MBP) stable up to 460 °C was synthesized using bithiophene and biphenyl as building blocks through Suzuki cross-coupling. The as-obtained MBP product exhibits green fluorescence peaked at 530 nm, and most interestingly, a two-photon fluorescence was observable from MBP upon excitation by an 800 nm femtosecond laser.