Thanks for the query.
Telugu Language Day or Telugu Bhasha Dinotsavam is celebrated on 29th of August each year. Telugu Language day is celebrated for the betterment of Telugu language and various funds and awards are given away that day. The date was chosen to coincide with the birthday of Gidugu Venkata Ramamurthy (1863 - 1940), famous Telugu writer and one of the earliest modern Telugu linguists and social visionaries.
Sources: Google.
Gidugu Venkata Ramamurthy - https://en.wikipedia.org/wiki/Gidugu_Venkata_Ramamoorty