TRI was first established in 1925 as an arm of the Planters’ Association of Ceylon, in order to enrich the tea industry through professional research findings. The institute had its early beginnings in Nuwara Eliya town with a representative nucleus of staff undertaking research in make-shift laboratories with very modest equipment and then transferred to the present location, the St. Coombs Estate in Talawakelle, in December 1929. Gradually TRI spreads into all tea growing areas of the country by establishing regional centres in Passara (Uva region), Kandy (Mid country region), Ratnapura (Low country region), Galle (Galle district), and Deniyaya (Matara and Hambantota districts). The two estates, St. Coombs in Talawakelle and St. Joachim in Ratnapura, which are operated under TRI, provide facilities to undertake research in cultivation and processing while making some earnings to the institute.
TRI is presently governed by the Tea Research Board of Sri Lanka which is under the purview of the Ministry of Plantations Industries. Tea Research Board consists of scholars of the field of research, management and economics.