Polycrystalline samples La0.67-xDyxCa0.3MnO3 (x=0~0.6) were prepared by traditional solid-state reaction method. The magnetization and resistivity of the samples were measured by PPMS (Quantum Design). The infrared absorption spectra (temperature scope: 20~300 K, frequency: 400~4400 cm-1) were collected by WQF-410 Fourier Transform Spectrophotometer. The substitution of Dy on La sites results in a decrease of the Curie temperature Tc and the magnetization, and also induces cluster-glass behaviors. The resistivity of the compounds is enhanced by Dy doped. Infrared absorption spectra provide the evidence of the variety of Mn-O-Mn bond length due to the Dy substitution and temperature changing. These results suggest that all of the magnetic coupling between Dy and Mn sublattice and La-Dy average ionic radius contribute to the magnetic and electronic character.