Four nano-rare earth ternary complexes of L-glutamic acid and imidazole RE(Glu)(3)ImCl(3)center dot H2O (RE=Ce3+, Pr3+, Sm3+, Dy3+, Glu= L-glutamic acid, and Im=imidazole) were. synthesized. Their composition was characterized with elemental analysis, IR, and molar conductance. The TEM image indicated that the complexes were regular shaped and the length was about 30 similar to 60 nm. The antibacterial activity test showed that all these complexes exhibited better antibacterial ability against Escherichia coli, Staphylociccus aureus, and Candida albican (MIC were about 180, 100, and 310 mu g/ml, respectively) and could be considered as broad-spectral antimicrobial. Their antitumor activity in vitro against leukemia K562 cells was measured using the MTT method. The results indicate that the four complexes possess strong inhibition effect on leukemia K562 cells. An approximately linear relationship is discovered between the relative inhibition rate and concentration, with the correlation coefficients R>0.7 and P<0.05, which is considered statistically significant.