Their movement was captured on camera hidden inside the forest on Monday night, they said.
"We are confident that the Tiger population has increased in the Sathyamangalam Tiger Reserve (STR) area. This was evident as the hidden camera inside the forest area has trapped the movement of the tigress with its cubs, I Anwardeen, Field Director, STR, said in a release.
He said Sathyamangalam is the fourth Tiger Reserve in the state and started functioning from last year.
Some forest officials said they also noticed the movement of a tigress and its cub in Kavarakkal Estate on Pollachi-Valparai ghat road on Monday night.