To investigate the effect of Herba Dendrobii extract on diabetic retinopathy (DR) through miR-223-3p/CARM1 axis.High glucose induced human retinal pigment epithelial cell line ARPE-19 to establish DR Model cells in vitro, and then treated with Dendrobium extract to observe the activity of DR Cells and the expression of miR-223-3p/CARM1 after intervention.Overexpression and inhibition of miR-223-3p or CARM1 related sequences were constructed and transfected into DR Cells.After high glucose induction, the activity of ARPE-19 cells decreased significantly, and the apoptosis rate increased significantly; after the intervention of Herba Dendrobii extract, the cell activity was significantly increased and apoptosis was significantly inhibited; the expression of miR-223-3p was significantly increased, and the expression of CARM1 protein was significantly decreased.Both the increase of miR-223-3p and the inhibition of CARM1 can significantly activate the activity of DR Cells and inhibit apoptosis.After the increase of miR-223-3p, the fluorescence activity of CARM1-WT was significantly inhibited, and the expression of CARM1 protein in DR Cells was significantly decreased.Inhibition of miR-223-3p on DR Cells was completely reversed by inhibition of CARM1 or Herba Dendrobii extract, and inhibition of CARM1 could be combined with Herba Dendrobii extract to further enhance the activity of DR Cells.Herba Dendrobii extract activates the activity of DR Cells, inhibits apoptosis and improves the progression of DR By regulating miR-223-3p/CARM1 axis.