The invention discloses application of a metal hydride/ palladium compound system in preparing a 1,3-dicarbonyl compound through cascade reaction in an electron-deficient alkene compound. The reactioncomprises the following steps of under the protection of nitrogen, suspending a palladium compound and metal hydride in a solvent, stirring, then adding the electron-deficient alkene compound, reacting at 0 DEG C to 100 DEG C for 0.3 to 10 hours, adding a saturated ammonium chloride water solution for stopping reaction, then extracting, drying by distillation, purifying through column chromatography, and thus obtaining the product of the 1,3-dicarbonyl compound. The hydride and a palladium compound catalyst used by the invention are reagents easy to get in the lab, so that the method is easier to operate, higher in safety, mild in conditions, and high in reaction yield compared with a common hydrogen hydrogenation method.