Tõnis Rätsep (born June 30, 1947) is an Estonian actor, musician, educator, poet, and playwright.

Tõnis Rätsep was born in Viljandi, one of two children to a father who was a dairyman and a mother who worked in a dairy laboratory. The family later relocated to Rakvere, where he attended primary and secondary schools, graduating from Rakvere Secondary School No. 1 in 1965. The same year he graduated from lessons at the Rakvere Music School, having studied bass accordion.

In 1968 he enrolled at the Tallinn University of Technology, majoring in energetics, graduating in 1972. Afterward, he enrolled in the Performing Arts Department of the Tallinn Conservatory (now the Estonian Academy of Music and Theatre), studying acting under instruction of actor and theatre pedagogue Voldemar Panso, graduating in 1972. Among his graduating classmates were Kersti Kreismann, Ivo Eensalu, Vello Janson, Rein Kotkas, Helle Meri (née Pihlak), Katrin Kumpan, Martin Veinmann, and Juhan Viiding.