The expression of miR-155 was significantly higher in LF from LSS group than in LF from LDH group (P < 0.01). miR-155 level was positively correlated with LF thickness (r = 0.958, P < 0.01), type I collagen level (r = 0.825, P < 0.01), and type III collagen level (r = 0.827, P < 0.01). miR-155 mimic increased mRNA and protein expression of collagen I and collagen III in fibroblasts isolated from LF, while miR-155 sponge decreased mRNA and protein expression of collagen I and III in fibroblasts.