In 1957, he gained admission to the University of Ceylon, Peradeniaya, where he was tutored by some of the best scholar’s of the country in the field of Sinhalalanguage and literature, such as Prof. D.E. Hettiarachichi, Prof. EdiriweeraSarachachandra, Dr. M.W. Sugathapala De Silva and Dr. SiriGunasinghe. The academic and cultural atmosphere prevailed in the university and his ardent love for the Sinhala language and culture paved the way for his subsequent academic and professional achievements.
In 1961, Prof. Disanayaka graduated from the University of Ceylon securing a First Class honours degree winning many prizes for academic excellence. Soon after his graduation he began his academic career as a lecturer in the Dept of Sinhala. As a young lecturer he chose the field of Modern Linguistics for his postgraduate studies. He received his MA in Linguistics from the University of California, Berkeley where he spent two years (1963-65) as aFulbright Scholar. He spent another year at the University College, Londonstudying Theoretical Linguistics. During his postgraduate life he was influenced by a number of leading linguists, notably Professors Dell Hymes , John Gumperz and Michalel Halliday. As a professional linguist, Prof. Disanayaka is a product of both American and British school of linguistic thought. His doctoral dissertation on The Word in Modern Literary Sinhala was submitted to the University of Colombo in 1980.