A young boy has died after being pulled from the bottom of a swimming hole in NSW’s Blue Mountains.

The seven-year-old was reported missing by his parents on Sunday afternoon at Jellybean Pool at Glenbrook, about 60km west of Sydney.

Family members pulled the unconscious boy from the water and started resuscitation attempts before paramedics took over.

He was taken to Nepean Hospital in a critical condition but later died.

NSW Ambulance inspector Peter Van Pragg said five crews plus a rescue helicopter were dispatched to the scene and paramedics did everything they could to save the boy.

“It is just so sad,” he said.

“These sorts of jobs have a significant impact on all the emergency services involved, but none more so than the family, and our hearts go out them.”

He said the incident was a tragic and timely reminder to take care near the water as the weather starts to warm up.

“In the blink of an eye, everything can change,” Mr Van Pragg said.

“Nobody intends for these tragedies to happen, but that’s the thing about accidents – they happen in second – but the impact can remain for a lifetime.”