Abstract <p>The influence of mixed red-blue light on plant development and medicinal properties is significant. To find an ideal combination of red-blue light for promoting the growth of <i>Dendrobium officinale</i> Kimura and Migo (<i>D. officinale</i>), this study examined four distinct proportions of red to blue LED light sources, using white LED light as a control group. Many methods in physiology and biochemistry were employed to assess the growth, physiology, and medicinal elements of <i>D. officinale</i>. The research indicated that blending red-blue light in a 3 : 2 proportion was optimal for the growth of <i>D. officinale</i> and the accumulation of secondary metabolites in <i>D. officinale</i>. At 28 days, the build-up of polysaccharides, polyphenols, and alkaloids was optimal, increasing by 119.96% (<i>P</i> &lt; 0.01), 1.66, and 30.44% respectively compared to the natural group. At 42 days, the accumulation of flavonoids peaked, showing a 99.11% increase (<i>P</i> &lt; 0.05) relative to the natural group. A red to blue light proportion of 3 : 2 was advantageous for managing <i>D. officinale</i> photosynthesis and osmotic mechanisms. On the 42th day, the greatest rise in the accumulation of overall chlorophyll and carotenoids was noted, escalating by 17.65 and 21.57% respectively in comparison with the natural group. On the 42nd day, there was an increase of 7.12% in MDA levels relative to the natural group. On the 28nd day, there was a 19.76% rise in soluble sugar content (<i>P</i> &lt; 0.01). These findings provide significant theoretical support for artificial cultivation of <i>D. officinale</i>.</p>