Six new 4-acyl pyrazolone derivatives and their complexes with the terbium nitrates were synthesized and characterized by mass spectra, elemental analysis, EDTA titrimetric analysis, UV spectra, infrared spectra, molar conductivity and thermal analysis. The results showed that pyrazolone derivatives formed good coordination with the terbium ions. The introduction of electron-donating group in the ligands not only increased the luminescence intensity and fluorescence quantum yield, but also enlarged the HOMO and LUMO energy levels of corresponding terbium complexes. All the complexes possessed high luminescence intensity and showed relatively high fluorescence quantum yields. These target complexes may have vast potential to be developed as luminescence materials in the future.