Hong Saeng (Thai: ห้องแซง, pronounced [hɔ̂ŋ sɛ̄ːŋ]) is a tambon (subdistrict) of Loeng Nok Tha District, Yasothon Province, Isan region (northeastern Thailand).

[1] Hong Saeng is a long time and secured home of Phu Thai ethnic group.

Originally, the area was called "Dong Pa Hong Ya Saeng" (ดงป่าฮ่องหญ้าแซง) and was distorted to be "Hong Saeng" in the present day.

[2] Hong Saeng considered as an area near the border of three provinces, namely Yasothon, Roi Et, and Amnat Charoen,[2] most of the area consisting of lowlands from central to western parts.

[3] Neighboring tambons are (from the north clockwise): Kut Chiang Mi, Samakkhi, Si Kaeo, and Pha Nam Yoi of Nong Phok District, Roi Et Province.