Girl seriously injured by falling tree branch at Parkdale in Melbourne's south-east

A young schoolgirl is in a serious condition and two other girls have head injuries after they were hit by a falling tree branch outside a Parkdale church in Melbourne's south-east.

St John Vianney's Primary School principal Shane Regan said the gum tree branch fell when about 150 schoolchildren were leaving mass at the parish next to the school just before 1:00pm.

"Unfortunately a stronger gust of wind brought down the branch and three little girls were injured by that branch," he said.

The parish is located on the corner of Brisbane Terrace and Warren Road in Parkdale, next to the primary school.

Paramedics treated all three girls at the scene before they were taken to the Royal Children's Hospital, an Ambulance Victoria statement said.

One girl was in a critical condition when she was taken to hospital.

By 3:00pm, her condition was listed as serious while the two other girls remained in stable conditions.

Mr Regan said the most seriously injured student was conscious and talking throughout the ordeal.

"She was in shock and she was upset and she was wanting her mum. She became far calmer when mum arrived," he said.

Mr Regan declined to give the exact ages of the students but said they were younger than Grade 4.

Parents were notified about the incident via SMS and could collect their children from school if they wished.

"Everyone is aware of the situation. The children are fine at the moment and are concerned for those who are injured," Mr Regan said.

The tree is located on parish land and Mr Regan said it had been checked by an arborist in the last two years.

"There have been no reports about the tree that have given us cause for concern," he said.

Mr Regan said the school would take any necessary action based on information from an arborist who inspected the tree after the branch fell.

A number of people have been killed by falling trees and tree branches in Victoria this year, including university professor and mother of two Allison Milner, who died when she was hit by a tree in Parkville in August.

Melbourne mother Angie Suryadi was killed in the same month when a tree crushed her family's car as they drove through the state's iconic Black Spur road after wild weather had lashed the state.

In July, a man and a boy were killed when a tree fell onto their car in the Dandenong Ranges in Melbourne's outer east.