A novel seven-core chalcogenide glass fiber was fabricated via extrusion. Firstly, two glasses, As₂Se₃ and As₂S₃, were prepared by distillation purification and melt-quenching. Then, an improved isolated extrusion method was used to fabricate the optical fiber preforms. In addition, a novel seven-core chalcogenide glass fiber of a complete structure was obtained with the protection of the high-temperature polymer layer, with the numerical aperture (NA) in the range of 1.20 to 1.45. Its loss was measured by the cutback method, with a minimum of 1.9 dB/m@4.4 μm. Finally, pumping with femtosecond laser from an optical parametric amplifier (OPA) yielded a supercontinuum covering 1.5--12 μm in a 14-cm long seven-core fiber, demonstrating excellent nonlinearity of this fiber. In summary, this fiber shows great potential in both mid-infrared research and technical applications.