Shots were fired from a car near St Brendan’s Primary School in Craigavon, Co Armagh.
The victim, a well known criminal, was hit a number of times during the gun attack just after 3 pm.
Local police boss Chief Inspector Jon Burrows said: “There are no words to describe the foolhardiness and complete disregard for the safety of the children and parents who were in the area at the time.”
Schoolchildren boarding a bus at the school gates are said to have witnessed the shooting.
BBC News NI’s home affairs correspondent Vincent Kearney said the victim is a well-known criminal.
The man is said to be receiving treatment to his injuries.
Police said they believe a black BMW 525 Sport that was found on fire in the Deramore Drive in Lurgan a short time later could be linked to the shooting.
Added Chief Inspector Burrows: “The area was very busy and we believe a number of people may have witnessed this shooting.
“We would ask anyone who has information to contact us as soon as possible so we can progress our investigation.”