Marie-Emmanuelle Verhoeven, 57, landed at Charles De Gaulle airport at 7.00pm on Thursday after India dropped extradition proceedings against her, sources said.
Following a court hearing on Wednesday, the Indian foreign ministry said it had let her leave the country on "medical and humanitarian grounds" and because France has undertaken to examine Chile's extradition request.
Verhoeven was arrested on the India-Nepal border, where she was on a Buddhist pilgrimage, on 16 February 2105 on a request by Chilean authorities, who suspect of involvement in the 1991 assassination of Jaime Guzman, a senator considered to have been one of the main backers of Pinochet's 1973-1990 dictatorship.
The killing was blamed on the far-left Frente Patriotico Manuel Rodriguez, which investigators claim Verhoeven belonged to, going under the pseudonym of "Commander Ana".
After her arrest in India she spent 16 months in a high-security prison before being released on bail.
She claims the charges are politically motivated, saying that she demonstrated against the dictatorship but had nothing to do with the assassination.
A German court agreed with her assessment in 2014, turning down the extradition request and releasing her six months after she was arrested at Hamburg airport.