The invention relates to a method for producing unsaturated fatty acid ester by the oxidative esterification. The method comprises the following steps: reacting small molecular alcohol and unsaturated aliphatic aldehyde as raw materials with molecular oxygen in the presence of a Pd-containing catalyst and one or more of solid metal compounds MxNy as the promoter by the one-step oxidative esterification to obtain the unsaturated fatty acid ester. The amount of the promoter is of 10<-6>-1.0g/ml, and at least one of the solid metal compound components is identical with one or more of the active components in the catalyst. The particle size of the promoter is of 5 nm-1,000 Mum has a shape of powder, particle, sphere or column. Compared with the prior art, the method has the advantages that the catalyst component loss is inhibited, the catalyst stability is improved and the catalyst service life is prolonged. In addition, the method is characterized in that the conversion and the selectivity are improved, the cost is reduced, the aldehyde conversion reaches 99.2%, and the ester selectivity reaches 90.23%.