Thi Tinh Nguyen, Tien Dung Nguyen, Xuan Thanh Dao, Truc Dat Chu, Xuan Binh Ngo, In Vitro Propagation of a Vietnam Endemic Lady’s Slipper Orchid (Paphiopedilum vietnamense O.Gruss & Perner), JHPR Volume 1, Journal of Horticulture and Plant Research (Volume 1) https://www.scipress.com/JHPR.1.1 Abstract: <i>P. vietnamense</i> O. Gruss & Perner is one of the endemic lady’s slipper orchids in Vietnam that has been known as an endangered species threatened with extinction due to over-collection. To protect<i> P. vietnamense</i> species,<i> In Vitro</i> propagation method needs to be established for producing plantlets that can be introduced back in wild, as well as commercialized. In this study, we examined the effect of basal culture medium, plant growth regulators, and AC on the micropropagation ability of <i>P. vietnamense</i>, which were collected from wild population in Thai Nguyen province, Northeastern Vietnam. We determined that the 0.2% HgCl<sub>2</sub> can be used in within 5 to 10 min for sterilizing axillary buds of <i>P. vietnamense</i>, resulting in 65.55% of disinfected samples. Moreover, the 1/2 MS medium supplemented with 2.0 mg 1<sup>-1 </sup>BA and 1.0 mg 1<sup>-1 </sup>NAA, which gave about 2.85 shoots/sample, was the most suitable for shoot regeneration and multiplication. In addition, the result also indicated that 0.5 mg 1<sup>-1 </sup>NAA and 1.0 g 1<sup>-1 </sup>AC gave the best results (88.89%) for root induction and plantlets Keywords: BA, <i>In Vitro</i>, Propagation, Slipper Orchid