〔Abstract〕 Objective To investigate the effect of demethylase obesity-associated protein(FTO) on the expression of tumor necrosis factor-α-stimulating gene-6(TSG-6) mRNA demethylation in keloid tissue and its role in scar formation. Methods Fresh keloid tissue(experimental group) and normal skin tissue(control group) were randomlyselected, and the expression level of TSG-6 in the experimental group and control group was detected by immunofluorescence method. A probe expressing TSG-6 mRNA sense and antisense chain were constructed for RNA pulldown, followed by Western blot detection of samples in each group with N6-methyladenine(m6A) antibody. Real-time fluorescence quantitative polynucleotide chain reaction(qPCR) and Western blot were used to detect the expression of TSG-6 mRNA demethylase and methylase in the experimental group and control group. The expression levels of FTO in experimental group and control group were detected by immunofluorescence assay. Results Immunofluorescence results showed that the expression level of TSG-6 in the experimental group was lower than that in the control group(P<0.01). Pulldown test results of biotin-labeled TSG-6 RNA showed that the m6A expression level of TSG-6 mRNA in the experimental group was lower than that in the control group(P<0.01). The results of qPCR showed that the expression level of FTO mRNA in the experimental group was higher than that in the control group(P<0.01). Western blot analysis showed that FTO protein expression in the experimental group was higher than that in the control group(P<0.001). Immunofluorescence results showed that the expression level of FTO in experimental group was higher than that in control group(P<0.001). Conclusion The demethylase FTO catalyzes the demethylation of TSG-6 mRNA and promotes the formation of keloid, which may provide a new idea and direction for clinical treatment of keloid.