In conclusion, we successfully synthesized and fully characterized two kinds of novel Rh/MelCOF catalysts, and realized the highly selective synthesis of N-methylamine by only using methanol as the methylation and hydrogenation source, and nitroarene as the raw material. Two kinds of Rh/MelCOF carrier materials were prepared by a simple heating and stirring method, and the relatively narrow pore size distribution was concentrated in 1.5 nm-5.7 nm. Rh is anchored uniformly on the two COF materials. According to XPS, it is found that the strong coordination bond of MelCOF has a strong interaction with Rh, which makes the catalyst have the catalytic performance of carrier and rhodium chloride to carry out the mono-N-methylation of nitroaromatic hydrocarbons. A series of functionalized nitroaromatic hydrocarbons with electron-donating and electron-withdrawing substituents, including heterocyclic or sterically hindered derivatives, have been effectively converted to corresponding N-methylamines with good to excellent yields under low catalyst support using Cs2CO3. On the other hand, according to the study of the reaction path, the reaction path here is different from the previously reported mechanism, and the reaction path with azobenzene as an intermediate is faster and much more selective. With the help of Rh/MelCOF, it is widely used to realize the high-value conversion of nitroaromatic compounds to a variety of Nmethylamines. The synthesis process using methanol as methylation and hydrogenation source is more economical and green. Currently, we are focusing modify and improve the stability of these novel COF-supported heterogeneous catalysts and exploring their more applications in challenging organic transformations.