Three teenagers have been taken to hospital after allegedly being hit by a ute in Melbourne's south-east on Friday afternoon.

Victoria Police have been told a driver in a black Mitsubishi Triton ute collided with the teens, believed to be students, just after 3pm on O'Sullivan Road. The incident took place near Glen Waverley Secondary College.

The vehicle came to a stop nearby, with a 44-year-old Springvale man assisting police with their enquiries. Police said the ute passenger remains outstanding.

Ambulance Victoria said Advanced Life Support and Mobile Intensive Care Ambulance paramedics attended the scene.

The teenage girl suffered upper and lower body injuries, and is in a serious but stable condition in The Royal Children's Hospital.

One of the teenage boys has upper and lower body injuries, and is in a serious but stable condition in The Alfred hospital.

Another male suffered minor upper body injuries and was taken to Box Hill Hospital in a stable condition.

Victoria Police want anyone who witnessed the incident, or has CCTV or dashcam footage, or any other information to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au