Effect of interchain coupling on the inversed polarization of a biexciton has been studied in the framework of a tightbinding approximation. It was found that a biexciton state is mainly confined in one chain even the interchain coupling is included. The inversed polarization will be enhanced remarkably with the interchain coupling in the case of a weak nondegenerate confinement. However, the inversed polarization will keep nearly unchanged for a strong nondegenerate confinement.