The amorphous metal-organic compounds (Ni-A-CA) were prepared by combining nickel node with organic ligands (adenine (A) and citric acid (CA)) via solvothermal method. Then, highly dispersed Pd/Ni-A-CA catalysts developed were fabricated by dispersing PdCl2 on amorphous support and reducing PdCl2 solution via freshly prepared NaBH4. The microstructure, morphology, and compositions of the obtained Pd/Ni-A-CA catalysts were comprehensively investigated by XRD, FT-IR, TEM, and XPS, etc. The results showed that Pd NPs were in high dispersed state and Pd NPs size diameter was 2.2 ± 0.3 nm. Besides, there existed a strong interaction effect between Pd NPs and amorphous Ni-A-CA support. The optimal temperature and hydrogen pressure were 90 °C and 2 MPa H2, respectively. Under this condition, the conversion of quinoline and the selectivity of 1,2,3,4-tetrahydroquinoline were about 99% over 3% Pd/Ni-A-CA catalyst for 70 min reaction duration. Furthermore, the Pd/Ni-A-CA catalyst also exhibited good catalytic stability and catalytic performance basically kept unchanged after 5 cycles.