The invention discloses a heterojunction-embedded photocatalyst with one-dimensional doping TiO2 and a preparation method and an application thereof. The catalyst has a one-dimensional structure, which contains TiO2/SnO2 heterojunction structure, or TiO2/ZnO heterojunction structure, or TiO2/SnO2 heterojunction structure and TiO2/ZnO heterojunction structure by modification with nonmetal doping. The required catalyst is prepared by chemical deposition method under the condition that crystal growth catalyst exists by alternate switching gas sources such as different precursors, impurity gas, etc. to realize the alternate growth of different semiconductors, which has higher photocatalysis degradation capacity of indoor contamination under ultraviolet light and visible light.