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Heavy metal resistant siderophore-producing bacteria (SPB) with plant growth promoting traits can assist in phytoremediation of heavy metal contaminated soil. We isolated siderophore producing bacteria from lead and zinc mine soil in Shangyu, Zhejiang, China. The isolate with highest siderophore production, strain SX9, was identi ed as Burkholderia sp. The strain SX9 produced catecholate type siderophore, with highest production at a pH range 6.0 to 8.0, a temperature range 20 to 30 °C and NaCl concentration below 2%. Siderophore production was highest without Fe 3+ and became gradually lower with increasing Fe 3+ concentration. Minimal inhibitory concentrations (MIC) of Pb 2+ , Zn 2+ , Cu 2+ and Cd 2+ were 4000, 22000, 5000 and 2000 μmol•L -1 , respectively. The strain SX9 was sensitive to doxycycline hyclate and rifampicin. The strain had a strong metal solubilization ability: the contents of Cu 2+ , Zn 2+ and Cd 2+ in the supernatant were 47.4%, 133.0% and 35.4% higher, respectively, in the strain SX9 inoculated cultures than in the not inoculated controls. The siderophore produced by strain SX9 could combine with Fe 3+ , Zn 2+ and Cd 2+ with good effectiveness. The plant growth promoting traits of the strain included indole acetic acid (IAA) production, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity and phosphate solubilization capability. Compared to uninoculated growth medium and SX9 culture supernatant, the germination rate of Lolium perenne seeds was higher when inoculated with the strain SX9 culture. In the experiment of seed germination, adding bacterial culture or supernatant could alleviate the toxicity of heavy metals to Lolium perenne seed germination. Under Cu 2+ and Zn 2+ stress, the strain SX9 promoted the germination rate. Taken together, the strain SX9 had properties bene cial in the microbial enhancement of phytoremediation of soil contaminated with heavy metals.