The method and process of resistance breeding of two species of flower were introduced in the book. The distant hybridization was used for lodging-resistant breeding of Platycodon Grandiflorus and the lodging-resistant offspring were obtained. The results show that the lodging-resistant offspring could be the phenomena of apomixes which was induced by pollen. The Si-ion implantation mutation breeding was used for cold-resistant breeding of Oenothera speciosa and the cold-resistant offspring were obtained that can overwinter in Beijing. The results show that the cold-resistant character can be steadily inherited.