BACKGROUND Heavy metal pollution in soils is often the result of multiple genetic sources and action paths. Simple identification of the sources of heavy metals is not enough to provide sufficient information for the control of regional heavy metal pollution. So, it is necessary to quantitatively calculate the relative contribution rate of various emission sources to determine the main pollution sources. The heavy metal contents in the surface soils of the Qinghai—Tibet Plateau (QTP) have a tendency of aggregation, and quantitative analysis of the sources of heavy metals should be emphasized. OBJECTIVES To understand the contents, spatial distribution, ecological risk and sources of heavy metals with the surface soils in a typical alpine agricultural area in Qinghai Province. METHODS The surface soil (0-20cm) samples were collected from Zeku County in the eastern Qinghai—Tibet Plateau (QTP). AFS, ICP-MS/OES were used to determine the contents of 10 heavy metals (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Zn). The contents and spatial distribution of heavy metals in the soils, as well as the comparison with the other typical agricultural soils in plain areas were studied. The level of contamination and ecological risks was analyzed using the enrichment factor (EF), geo-accumulation index (Igeo) and the potential ecological risk index (PERI). The principal component analysis-absolute principal component score-multiple linear regression (PCA-APCS-MLR) receptor model was identified as the potential source of heavy metals for the study area. RESULTS (1) The average content of As exceeded the soil environment standard and the national background value. The average contents of Cd, Cr, Cu, Co, Ni, Zn, Pb and Hg were 0.14, 63.15, 23.84, 13.85, 30.65, 74.96, 23.2, and 0.02mg/kg, respectively, that were all far lower than the screening standard of soil environmental quality. Compared with the national surface soil background values and the surface soil background values of Qinghai Province, the contents of Cd and Hg were lower, while the contents of Co, Cr, Ni, Pb and Zn were slightly higher, and the content of Cu was close to the background value. The content of Mn ranged from 448mg/kg to 1286mg/kg, with the average 774mg/kg, which exceeds the national and Qinghai provincial background values. The spatial distribution characteristics of heavy metals were obvious. The contents of As, Cu, Cd and Cr were higher in the northern region. The highest contents of Co, Zn and Ni were around Maixiu Town in the northwest region for the study area. The content of Hg was low in the whole region, but slightly higher in the west than in the east. Pb showed the characteristics of sporadic high points. Mn was significantly higher in the eastern region than in the western region. In the whole study area, the contents of heavy metals in the northern and northeastern regions were higher than those in the western and southern regions. Compared with other regions of QTP, such as Qinghai Lake Basin, soils along highways, Yushu County, the surface soils of Zeku County had higher contents of As and Mn. The contents of Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn in the study area in Qinghai Province were higher than those in the soils around Qinghai Lake Basin, but lower than those along the highways and in Yushu County where human activities were abundant. Compared with the farmland soils in Sanjiang Plain, Huaibei Plain and other typical plain areas, the contents of heavy metals in Zeku County, as a typical alpine farmland area, were mostly lower. (2) The ecological risk of heavy metals in soils of Zeku County was evaluated by EF, Igeo and PERI. The results showed the value of EF was in the order of As(2.33)>Mn(1.27)>Ni(1.17)>Co(1.16)>zinc(1.15)>Pb(1.11)>Cr(0.92)>Cd(0.82), which indicates that As has moderate enrichment and other elements have mild enrichment in the soils. TheIgeo of 10 heavy metals was in the order of Cd(−1.02)