A teenager is fighting for his life days after he was found pinned under gym equipment at a PCYC gym north of Brisbane.

It is understood Ben Shaw, 15, had been working out on the bench-press at the Pine Rivers gym on Tuesday night when equipment came down on his neck about 8pm.

Ben Shaw remains in a critical condition at Lady Cilento Children's Hospital. Credit:Facebook

7 News reported that a staff member found the teenager about 20 minutes later, pinned under a 98-kilogram benchpress.

He was given first aid by staff and other gym members before paramedics rushed him to Lady Cilento Children’s Hospital, where he remained in a critical condition on Thursday.