The hypocotyls of mature seeds, hypocotyls of immature seeds and callus of tea ‘Fuyun 6’ and ‘Tieguanyin’ were used as materials, and the hairy root induction rate was used as an indicator to explore the bacterial concentration, Agrobacterium rhizogenes strain, explant type and preculture time on the induction of hairy roots. The results showed that: (1) the induction rate of hairy roots increased first and then decreased when the bacterial concentration OD₆₀₀ was in the range of 0.4 to 1.2. At OD₆₀₀ = 0.6, ATCC15834 had the highest hairy root induction rate of 23.96%, while at OD₆₀₀ = 0.8, A4 and K599 had the highest hairy root induction rates of 10.51% and 13.11%, respectively. (2) All three kinds of A. rhizogenes can induce hairy roots in tea plants, but their rooting abilities are different, of which ATCC15834 has the strongest rooting ability, for ATCC15834, K599 and A4, the ability of hairy root induction on tea plant was declining in turn. (3) The induction rate of hairy roots is related to the explants. The hypocotyls of mature seeds of tea plants can be induced to produce hairy roots, and the induction rate is ‘Fuyun 6’> ‘Tieguanyin’, while the hypocotyls of immature seeds and callus are difficult to produce hairy roots. (4) Callus without preculture and the preculture time of 1-2 days is easy to brown and cannot produce hairy roots, while callus precultured for 3 days can produce hairy roots after infection, with an induction rate of 1.85% (‘Fuyun 6’) and 0.59% (‘Tieguanyin’). (5) Genomic integration and transgene expression of hairy roots of mature cotyledons of ‘Fuyun 6’ and ‘Tieguanyin’ were confirmed by polymerase chain reaction (PCR) detection and betaglucuronidase (GUS) assays. The above results showed that ATCC15834 had the highest induction rate of hairy roots with hypocotyls of mature seeds of ‘Fuyun 6’ when OD₆₀₀ was 0.6. These findings provide a theoretical basis for improving the tea tree genetic transformation system mediated by Agrobacterium rhizogenes, and is of great significance to the optimization of the high efficiency genetic transformation system and the development of new receptors in tea plants.