Objective：To investigate the structure, antioxidant, antimicrobial and biocompatibility of rosmarinic acid and zinc (II) complexes. Methods：The structures of zinc (II) complexes with rosmarinic acid were analyzed by scanning electron microscopy, infrared and ultraviolet-visible spectroscopy. The effects of rosmarinic acid and zinc (II) complexes with rosmarinic acid on the proliferative activity of osteoblasts were compared by cell proliferation assay, the antioxidant properties of both of them were analyzed by ferric ion reducing antioxidant power assay and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) ammonium salt free radical (ABTS+) scavenging assay. The minimum inhibitory concentration (MIC) assay compared the inhibitory activities of the two against Staphylococcus aureus. Results：The rosmarinic acid-zinc (II) complex (RA-Zn) was successfully synthesized, and by the fifth day, the osteoblast proliferation-promoting of RA-Zn was superior to that of RA (P<0.05). 200 μmol/L RA-Zn scavenged higher levels of ABTS+ cationic free radicals and reduced Fe3+ than RA (P<0.05). RA above 400 μmol/L inhibited Staphylococcus aureus activity (P<0.05), whereas there was a statistically significant difference in the inhibitory activity of RA-Zn from a concentration of 25 μmol/L (P<0.05). Conclusion：The antioxidant and antimicrobial properties were enhanced by the complexation of rosmarinic acid and zinc ions, which promoted osteoclast proliferation.