About 100 people have been involved in the frantic search for Shayla Phillips in southern Tasmania since she went missing on Wednesday afternoon.

State Emergency Service crews conducting a close-to-ground search spotted her on a steep slope in dense bushland near Halls Rd just after 4pm on Friday, hundreds of metres from where she went missing near Stormlea Rd.

Inspector Gavin Hallett said Shayla was able to walk but appeared disoriented, and police reunited her with her mother as soon as they could.

"It was obviously very emotional when I passed the happy news on to mum. She was very grateful," he told reporters.

Shayla has been taken to hospital for medical assessment after spending two nights in the remote area where temperatures dropped to 11C.

"Dehydration would be an issue so certainly that's something they'd be wanting to fix as soon as they can," Insp Hallett said.

The area where she was found was about 500 metres from the nearest home, and had previously been searched from the air, but not on foot.

Insp Hallett said he knew that search crews, combing their way through dense bushland, simply had to persevere.

"We've said all along this was a search and rescue operation, there was nothing at all to indicate that anything untoward had happened, we knew that if we just kept pressing away we would find her," he said.

"It was certainly a great relief to find her safe and well."

It's understood the search crew saw her about 100 metres from where they were.

Thermal imaging drones, helicopters, divers and sniffer dogs from Victoria Police were involved in the search.

Shayla had been playing outside with dogs from a neighbouring property when she was last seen about 2.30pm on Wednesday, wearing pink leggings, a cream top, and gumboots.

When her mother went to check on her after about half an hour later, Shayla and the dogs were gone.

Tasmanian Premier Peter Gutwein said the news was heartwarming and thanked everyone who helped with the search.

"For the last 48 hours, Tasmania's thoughts and prayers have been with Shayla, her family and loved ones wishing for her to be found safely," he said.

"We are all so pleased to see little Shayla reunited with her family and friends following this positive outcome."

Australian Associated Press