In the present study, the GTT and ITT assay showed that the H-126 group mice had worse glucose tolerance and insulin sensitivity, indicating that the overexpression of miR-126b-5p aggravated obesity in C57BL/6 mice; this also suggests that inhibiting the expression of miR-126b-5p is a significant potential target for inhibiting obesity. The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.