The solid complex of lanthanum nitrate hydrate with 4-(p-dimethylaminobenzaldehydeamino)-4H-1, 2, 4-triazole(L)LaL₃(NO₃)₃·(H₂O)₂·(C₂H₅OH)₂ was synthesized in dry N₂ atmosphere and absolute alcohol. The composition of the complex was determined by chemical and elemental analyses. The crystal structure showed that La₃₊ was coordinated by ten oxygen atoms with three nitrate, two water and two alcohol molecules. Characterized by elemental analysis, infrared spectroscopy, and solid fluorescence, the experimental results showed that the free ligand is a thermally stable material, and emitted intensive blue fluorescence at the peak wavelength of 451 nm. Compared with the fluorescence emission of free ligand in solid-state,the emission of complex of LaL₃(NO₃)₃ ·(H₂O)₂·(C₂H₅OH)₂red-shifted to 464 nm and exhibited stronger blue fluorescence.