Diana Tea Company is a tea-producing company, which was promoted by Late Radheshyam Singhania in 1976. Radheshyam Singhania had bought this company from Nawab Gulam Jabbar and family. Then, the company had only one garden producing 242,000 Kg of tea and a book loss of Rs 37.6 lakhs. The company is among top five producers of tea in the Dooars region. It has four tea gardens, namely Baintgoorie Tea Estate, Goodhope Tea Estate, Ambari Tea Estate and Diana Tea Estate.