A novel π-conjugated polymer, poly(3,4-bisphenyl- N- n-hexyl-pyrrole-2,5-dione), was synthesized by dehalogenation polycondensation with the zerovalent nickel complexes (the Yamamoto method), of which the chemical architecture was based on the polyarylenevinylene having a fixed cis-vinylene group. This polymer showed high solubility in common organic solvents, high spin-castability and high thermal stability up to ca. 400°C and the T g of 152°C. The dilute polymer solution (THF) showed the greenish yellow photoluminescence with the maximum at 526 nm.