A two-line restorer line for polyploid rice and breeding method therefor. The method comprises: a. determining a hybrid parent of a breeding restorer line; b. breeding a restorer line of indica-japonica type, or breeding a restorer line of japonica-indica type, and performing backcrossing or composite crossing after parental hybridization; c. selecting a single strain that meets a breeding objective, performing composite crossing again, and performing a first molecular marker test; d. comparing and selecting a single strain having good traits, and performing continuous self-crossing until the strain is basically stable; e. selecting a stable strain having good traits and having a tested molecular marker; f. performing test crossing with different types of polyploid sterile lines using a preferred strain as the male parent; and g. choosing a good hybrid combination and a restorer line thereof. Good strains of restorer lines for polyploid rice are bred using a combination of a restoring ability of a photo-therm
