The invention relates to the technical field of organic synthesis, in particular to a supported metal catalyst, a preparation method and application thereof, and a synthesis process of N-methylmorpholine. The supported metal catalyst is prepared from an Al2O3-TiO2 supporter and active metal supported on the Al2O3-TiO2 supporter, and the mass of the active metal accounts for 15-30% of the mass of the supported metal catalyst. The catalyst is good in stability, good in activity and good in catalytic effect, the conversion rate of morpholine raw materials is high, and the synthesis yield of the N-methylmorpholine is high.