The Department of Agriculture was established since October 1, 1972 under the Revolutionary Decree No. 216 dated September 29, 1972 by merging the former Department of Agriculture and the Rice Department. The union was aimed to facilitate coordination among the Departments and officers as well as to streamline its function to enable a more efficient implementation of is mandates.

          The 15 pioneering units of the Department of Agriculture were the Office of the Secretary, Finance Division, Personnel Division, Planning Division, Rice Division, Field Crops Division, Horticulture Division, Sericulture Division, Rubber Division, Agricultural Engineering Division, Plant Pathology Division, Entomology and Zoology Division, and Agricultural Chemistry Division, A total of 95 research centres, stations and plant quarantine stations were then established throughout the country.

          Since its establishment the Department of Agriculture had undergone reform. In 1982, a Royal Decree dated April 25, 1982 was promulgated to re-structure the functions of the Department to be in line with the National Research Agenda. Following the Re-organization, the Department units comprised of Office of Secretary, Finance Division, Personnel Division, Planning and Technical Division, Agricultural Toxic Substances Division, Entomology and Zoology Division, Agricultural Chemistry Division, Agricultural Engineering Division, Botany and Weed Science Division, Plant Pathology and Microbiology Division, Farming System Research Institute, Rice Research Institute, Horticulture Research Institute, Field Crops Research Institute, Rubber Research Institute and Sericulture Research Institute. A total of 94 research centres and stations were established nationwide.

          On September 30, 1992 a Royal Decree was issued to re-structure the Department of Agriculture aimed to regionalize the Department’s function. The former Farming System Research Institute was reformed into eight regional Office of Agriculture Research and Development. The regional offices have headquarters in Chiang Mai, Khon Kaen, Phitsanuloke, Chainat, Ubonratchathani, Chantaburi, Suratthani and Songkhla.

          In 2002, by virtue of the Ministerial Regulation issued on October9, 2002 by the Ministry of Agriculture and Cooperatives had re-structured the Department of Agriculture to ensure the effective implementation of program to be more responsive to the trends of agricultural developments in the national and international community.

          In 2006, the former Rice Research Institute was upgraded as Rice Department, and in 2009, the former Sericulture Research Institute was upgraded to have a status as Department level and was named Queen Sirikit Sericulture Center under Her Majesty the Queen’s patronage.