Salvianolic acid A is extracted from the root of Salvia miltiorrhiza Bge. It has anti-oxidative capabilities. It can reverse paclitaxel resistance through suppressing transgelin 2 expression by mechanisms involving attenuation of PI3 K/Akt pathway activation and ABC transporter up-regulation. It has inhibitory effect on Cu2+ mediated human LDL oxidation through chelating Cu2+ and scavenging free radicals. It inhibited proliferation, caused cell cycle arrest at the S phase, and induced apoptosis dose dependently to the two kinds of cancer cells. It positively regulates PTEN protein level and inhibits growth of A549 lung cancer cells.