A method for selectively breeding a polyploid two-line hybrid rice plant, the selective breeding method comprising: determining a tetraploid rice plant photo-thermo-sensitive male sterile line having the genetic feature of PMeS (polyploid meiosis stability) and a tetraploid rice plant restored line having the genetic feature of PMeS; performing hybridization using an Indica/Japonica-restored or Japonica/Indica-restored hybrid combination; hybridizing and generating a tetraploid rice plant hybrid using the tetraploid rice plant photo-thermo-sensitive male sterile line and the tetraploid rice plant restored line; breeding a stable tetraploid rice plant hybrid combination and determining said combination to be a polyploid two-line hybrid rice plant combination. The breeding method utilizes the powerful heterosis of a polyploid rice plant to transform existing diploid heterosis into the heterosis of a polyploid "two-line" hybrid rice plant. Using the method may breed new varieties of polyploid two-line hybrid ric
