Stewart said the man was described as a Caucasian in his 40s. He fled in the opposite direction when the girl sought help.
The man was about 1.85m tall and had very short hair or was possibly bald. He was wearing camouflage-coloured trousers, a dark grey-coloured T-shirt and carrying a camo backpack.
Police are seeking witnesses to the incident or any other reports of similar behaviour in the area recently.
Any information should be provided to Stewart on (03) 363 5243.
Stewart encouraged families to talk to their children about any behaviour that made them feel uncomfortable.
"This girl did the right thing by briskly crossing the road to see if she was being followed, before approaching a member of the public and seeking help.
"During a situation such as this, 111 should be called as soon as possible. If it's not an emergency but you still have concerns, talk to an officer at your local police station," Stewart said.