In conclusion, we have firstly developed visible light mediated photocatalytic selective N-methylation of amines with a bar of CO2 as a sustainable C1 source in presence of NaBH4 as a reductant. According to the optimization of reaction conditions, affording the high selective products of methylamines in excellent yields. MOF as a good crystallinity can maintain shape and structure stable after reaction of N-methylation of amines, which has the potential to be recycled.