Ethynylene-containing benzo[1,2-b:4,5-b′]dithiophene derivatives 1a–c (BPEBDT, BTEBDT and BHPEBDT) were designed and synthesized. Their physicochemical properties were studied by absorption spectra and electrochemistry. 1a–c displayed high field-effect transistors performance, a mobility up to 1.17 cm² V⁻¹ s⁻¹ with on/off current ratio of 10⁷ was achieved.