The Royal Forest Department (Abrv: RFD; Thai: กรมป่าไม้, RTGS: Krom Pa Mai) is a department in the Ministry of Natural Resources and Environment (MoNRE), part of the Government of Thailand.

[1] A British forester, Herbert Slade, former Deputy Conservator of Forests in Burma, served as the first director of the department.

[2] In its early days the department focused on obtaining tax revenue for the use of forests rather than conservation, although its conservators expressed concern about unsustainable harvesting of teak in Thailand's northern forests.

Formerly the agency controlled Thailand's national parks but in 2002 they were taken over by the National Park, Wildlife and Plant Conservation Department (DNP), also part of the Ministry of Natural Resources and Environment.

Today, the agency aims to monitor forests, coordinate research, encourage community forest management, conserve forest land and monitor the wood industry.