The film is based on the much-debated story of Professor Ramchandra Siras, who was suspended from his job because of his sexual orientation.
"#Aligarh is exceptionally poignant, moving and heartbreaking in equal measure....A relevant and important film of our times," Johar tweeted after attending a screening of the film.
Actor Manoj Bajpayee plays the role of the professor and Rajkummar Rao will be seen as a journalist in "Aligarh", which Johar said is a "must watch" for everyone.
"Aligarh" will release on February 26.