[Background] The Taihu Lake basin, covering the Taihu Lake watershed and the River Area of southeastern China, is the highly developed region in China, and the soil loss caused by intensive human activities have been received much attentions in recent years. [Methods] To study the soil erosion situation of the Taihu Lake basin in the last 10 years, this article analyzed the soil erosion situation and its spatial distribution based on the remote sensing survey data of two periods by the Ministry of Water Resources, acquired the change trend during 2002 to 2011, and evaluated quantitatively the soil erosion situation with erosion index (EI) in the Taihu Lake basin. [Results] The total soil erosion area of the Taihu Lake basin in 2011 was 22 872.59 km², among it Taihu Lake watershed accounted for 1 064.58 km² and the River Area of southeastern China for 21 808.01 km². The main erosion intensity was light erosion in the Taihu Lake basin. However, the Taihu Lake watershed had the more percentage of slight erosion area, while the River Area of southeastern China had more percentage of strong, ultra strong and severe erosion area. From the administrative division perspective, Fujian Province had the most soil erosion area in the Taihu Lake basin. Zhejiang Province took the second place in soil erosion area and the main erosion was light and medium erosion. Anhui Province had the most erosion area of strong, ultra strong and severe relatively, which accounted for 23.42% of the soil erosion. Jiangsu Province and Shanghai had the least soil erosion area and there were nearly only light and medium erosion. From 2002 to 2011, the soil erosion area of the Taihu Lake basin had a decreasing trend in general. The total decrement area was 10 811.14 km² and annual average decrement area was 1 201.24 km². However, the area of light, moderate and severe erosion decreased and the area of very severe and extremely severe erosion increased. EI is a comprehensive index to assess soil erosion degree. The larger index value indicates more serious erosion. The EI in Taihu Lake watershed was 0.33, while it in the River Area of southeastern China was 1.65 in 2011. The EI was much higher in the River Area of southeastern China, indicating that the soil erosion was more serious as a whole. From 2002 to 2011, EI in the Taihu Lake basin decreased, which explained the soil erosion situation improved in general. But the EI obviously increased in a few areas, such as Zhuji, Taizhou, Wenling of Zhejiang Province and Minqing, Minhou, Putian, Xiamen of Fujian Province, exceeding 1.5 units. [Conclusions] Taihu Lake watershed showed less serious erosion than the River Area of southeastern China. It was also obvious to know that in the most areas of the Taihu Lake basin, the soil erosion area decreased from 2002 to 2011. However, there still were some areas where the erosion area and degree increased. Therefore, we suggested that these areas should be key controlling regions and there should be the countermeasures to prevent further soil erosion.