[Objectives] Jiangcheng is located in the priority area of biodiversity conservation in Xishuangbanna, where the diversity of reptiles is unclear and reptile resource survey is lack in history. Here, we conducted seven surveys for reptile diversity in Jiangcheng from May 2019 to September 2020. [Methods] Comprehensive surveys have been conducted to evaluate diversity of reptiles by using the fixed line transects method. A total of 207 survey lines were set up, covering a wide range of diverse habitats at different altitudes. The time span of each day is from 8:00 am to about 04:00 am of the next day. Collected specimens were brought back to the laboratory for identification. We use GrcGIS and Excel for data mapping and statistics. For data analysis, we used Berger-parker index (I) to determine dominant species, Margalef index (DMg) to determine species richness, and G-F index (DG-F) to analyze family and genus diversity. [Results] A total of 51 species of reptiles were recorded in Jiangcheng, which belong to 2 orders, 17 families, and 39 genera. 17 species (33.3%) are endangered in China and one Class-I (1.9%) and 7 Class-II (13.7%) nationally protected reptiles were recorded. The dominant species are Hemidactylus bowringii (I = 13.3%), Pareas macularius (I = 11%), while the rare species are Platysternon megacephalum, Cyclemys oldhami, Varanus salvator and Python bivittatus in Jiangcheng. We found 2 newly identified species which are namely Pareas geminates and Trimeresurus goui. Two species were new records. One of them, Parafimbrios lao, is the new record in China and the other, Pseudoxenodon karlschmidti, is the new record in Yunnan Province. All species can be divided into 6 ecological types, which are residential (3.92%), arboreal (17.65%), bushwood rocky (45.10%), arboreal aquatic (23.53%), aquatic (5.88%) and soil (3.92%, Fig. 2). Form the taxon of all, the Testudofomes have high dependence on the aquatic ecological environment, and the Lacertilia and Serpentes have a high dependence on the forest ecological environment. The soil and the residential type are endemic to the Serpentes and Lacertilia, respectively. The bushwood rocky has the highest richness index (DMg = 3.548) with high species evenness and the best stability. On the contrary, residential (DMg = 0.198) is the lowest richness index with low species evenness and poor stability (Table 1). The vertical distribution shows a certain regularity. The mountain slope (700﹣1 500 m) has the most abundant species, with 47 species whereas the Piedmont ravine and the mountain top are less distributed, with 10 and 4 species (Fig. 3). There are many species of single genus in reptiles (G = 3.506 5, F = 8.406 0). Species are mainly in the Oriental boundary, and has a relationship with the Himalayas-Hengduan Mountains. According to this survey, road killing is the most direct factor leading to the threat of reptiles, and 2/3 of the survey data comes from road killing, involving 35 species, especially Pareas macularius and Bungarus wanghaotingi. In addition, overharvesting has made some economically valuable species become rare, such as turtles and pythons. [Conclusion] Jiangcheng is rich in reptile species diversity, and this survey makes up for the gap in the literature on reptile diversity in this area. Jiangcheng is also a typical area of the biodiversity hotspot for studying the reptile diversity of rainforest. We suggest that the existing forest distribution pattern should be maintained, as well as keep studying, monitoring and conservation of reptile diversity into the future.