Abstract: With the rapid development of industry and agriculture, heavy metal pollution in soil has become more serious. Phytoremediation technology is widely used in cleaning up contaminated soil due to its low cost and no secondary pollution. However, the low bioavailability of heavy metals in soil and the low biomass of many hyper accumulators affect the phytoremediation of heavy metal contaminated soils. Low molecular weight organic acids (LMWOAs) are considered to apply in the remediation of contaminated soil because they can improve the mobility of heavy metals in soil and promote the release of heavy metals bound soil, therefore enhancing the activity of heavy metals in soil. Salix variegate Franch. is often used as engineering species for phytoremediation due to its good performance in terms of tolerance and accumulation of heavy metals. In order to reveal the application potential of exogenous organic acids in enhancing phytoremediation of Cd contaminated soil, pot experiments were conducted. The changes of soil Cd forms and the Cd accumulation characteristics of S. variegata were studied under different concentrations of exogenous oxalic acid and tartaric acid treatments. The results showed that exogenous tartaric acid treatments significantly reduced the content of non-available Cd in soil, increased the content of exchangeable Cd, promoted the Cd accumulation of S. variegata, and significantly increased the bioaccumulation coefficient of plants. Compared with the control treatments, 5 mmol/kg tartaric acid treatment significantly increased the Cd accumulation in aboveground, underground parts and whole plant under by 62.2%, 75.9% and 78.4%, respectively, and enhanced the bioaccumulation coefficient of aboveground and underground parts by 173.0% and 178.8%, respectively. However, the addition of oxalic acid had no significant effect on the content of available Cd in soil, and the content and accumulation of Cd in all organs of S. variegata. Therefore, the addition of 5 mmol/kg tartaric acid enhanced the ability of S. variegata to remediate Cd in soil, because it increased the exchangeable and available Cd content in soil. This method is suitable for phytoremediation of Cd contaminated soil.