Kampong Tralach District is a district in the south east of Kampong Chhnang Province, in central Cambodia. The district capital is Kampong Tralachtown located 37 kilometres south of the provincial capital of Kampong Chhnang by road. The district shares a border with Kandal province to the south and Kampong Champrovince to the east. The Tonle Sap river runs through the district crossing roughly from north to south.
The district has significant road infrastructure and National Highway 5 which runs from Phnom Penh to Poipet crosses the district from north to south. Kampong Tralach District is one of the smaller districts in Kampong Chhnang province by land area but has one of the largest district populations in the province due to well irrigated land and good transport infrastructure. National Road 138 starts at Kampong Tralach and runs across the district to its terminus at Chleb in TuekPhos district. Numerous smaller tertiary roads run either to the nearby national railway line or to the Tonle Sap.
Kampong Tralach is the site of the former capital of Cambodia at Lovek. Lovek was Cambodia's main city after the Siamese King Borommaracha II sacked Angkor in 1431. The new capital was located on the banks of the Tonle Sap river, halfway between Phnom Penh and the lower end of the Tonle Sap lake. This new site was chosen to be more defensible than Angkor. The city became a wealthy trading centre and attracted various Europeans traders and missionaries through the 16th and 17th centuries