Abstract: To understand the spatial distribution of total mercury (THg) and methyl mercury (MeHg) levels in sediments of park lakes in Shanghai City, the samples were collected from total 24 park lakes, including the central urban (CU) and the suburbs (SU) areas, respectively. The concentrations of THg and MeHg, and other parameters in sediments were determined and the risk of Hg pollution was assessed using geo-accumulation index methods. The results showed that the concentrations of THg (mean: 222.6 ± 138.4 μg/kg) and MeHg (mean: 0.52 ± 0.51 μg/kg) in the surface sediments of lakes in CU were significantly higher than those (mean: 91.8 ± 87.1 μg/kg THg; mean: 0.29 ± 0.26 μg/kg MeHg) in SU (p< 0.01). Moreover, THg and MeHg in the sediments were positively correlated with loss on ignition (LOI) (p< 0.05), while a weak correlation between the ratio of MeHg to THg (MeHg/THg) and LOI, indicating that organic matter in sediments may play an important role in inhibiting Hg methylation. The geo-accumulation index of THg revealed that lakes in CU was slightly polluted by Hg, however, lakes in SU was not polluted, indicating that the potential environmental risk of Hg in the surface sediments of park lakes could be low in Shanghai City.