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This study was conducted to examine the effect of plant growth regulators on the rooting and growth of <i>Rhododendron micranthum</i> Turcz., a rare plant in South Korea. Indole-3-butyric acid (IBA) 150, 250, 350 mg·L^{<span style="font-variant: small-caps;">−1</span>} and α-naphthaleneacetic acid (NAA) 50, 150, 250 mg·L^{<span style="font-variant: small-caps;">−1</span>} treatment groups were established and cutting was performed in a commercial growth medium in March 2021 with 3 replications of 10 plants per group. After 70 days, the longest initial root growth was observed under the NAA 150 and 250 mg·L^{<span style="font-variant: small-caps;">−1</span>} treatments. Moreover, the number of roots and percentage of rooting were slightly higher in NAA 150 and 250 mg·L^{<span style="font-variant: small-caps;">−1</span>}, indicating that these treatments were more effective in promoting plant growth. The above-ground part of plants treated with NAA 150 and 250 mg·L^{<span style="font-variant: small-caps;">−1</span>} had a taller plant height, longer and wider leaves, and a greater number of leaves compared to other groups. Accordingly, the survival rate of plants treated with NAA 150 and 250 mg·L^{<span style="font-variant: small-caps;">−1</span>} was higher than 80%, suggesting well-established roots and excellent above-ground growth. Therefore, treatment with growth regulator NAA at 150 and 250 mg·L^{<span style="font-variant: small-caps;">−1</span>} is considered beneficial for the cutting of <i>R. micranthum</i> Turcz.