In order to find a new type of PLLA high temperature crystallization nucleating agent, three kinds of palladium compounds, palladium chloride, Bis (triphenylphosphine) palladium (II) dichloride and 1,4-Bis (diphenylphosphino) butane-palladium (II) chloride were selected to add to PLLA, and PLLA / palladium compounds were prepared by melt blending based on different contents of palladium compounds. This work presented the effect of palladium compounds on the crystallization behavior and crystalline structure of PLLA with differential scanning calorimetry (DSC), polarizing optical microscope (POM) and X-ray diffraction (XRD).The results revealed that palladium chloride, Bis (triphenylphosphine) palladium (II) dichloride hindered the crystallization and 1,4-Bis (diphenylphosphino) butane-palladium(II) chloride promoted the crystallization. In the cooling crystallization process, when the amount of 1,4-Bis (diphenylphosphino) butane-palladium (II) chloride was 0. 8%, the corresponding crystallization peak temperature (Tc) rose from 103.92 ℃ to 126.57 ℃ and crystallization enthalpy (△Hc) increased from 31.52 J/g to 52.82 J/g, respectively. In the study of isothermal crystallization, the results showed that the Avrami exponent n was between 3 and 4, which implied the crystal morphology was spherulitic, and this means the crystal growth manner, crystalline structure and crystal form did not change. All these suggest that 1,4-Bis (diphenylphosphino) butane-palladium(II) chloride is a new type of PLLA nucleating agent, and more research is needed to understand its nucleation mechanism.