Abstract: In order to study the effect of Trichoderma sp on the number of microorganisms in the roots and rejuvenation matrix of Camphora officinarum Nees, the rejuvenation matrix of Camphora officinarum Nees was used as the cultivation matrix. Through the cultivation test of Camphora officinarum Nees seedlings, the Trichoderma sp with concentrations of 1.0 g/L, 1.5 g/L and 2.0 g/L were irrigated once every 15 d for three consecutive times, and the test indexes were measured after 60 d. The results showed that Trichoderma sp could significantly improve the root activity and root length, surface area, volume, average diameter and other root growth indexes of Camphora officinarum Nees. The concentration of 1.5 g/L Trichoderma sp treatment had the most significant effect on the root activity and root growth of Camphora officinarum Nees. The root activity was 223.26 μgTTF·g⁻¹FW·h⁻¹,the length was 2161.36 cm, the surface area was 251.72 cm_², the volume was 102.83 cm³, the average diameter was 0.581 mm. Which were 88.69%, 31.05%, 50.44%, 36.09% and 72.40% higher than that of the control group. At the same time, Trichoderma sp can also significantly increase the number of microorganisms in the rejuvenation matrix, and the effect of 2.0 g/L Trichoderma sp treatment was more significant. The total number of microorganisms was 44.37 × 10⁶ CFU·g⁻¹, which was 92% higher than that of the control group.