Almost 60 per cent of NSW voters support pill testing at music festivals despite the state government's refusal to consider it, exclusive new polling reveals one week after two people died at a dance party.

The Premier, Gladys Berejiklian, last week set up an expert panel to investigate how to make music festivals safer after two suspected drug overdoses at the Defqon 1 dance festival in Penrith last Saturday.

But the panel will not consider the merits of pill testing, Ms Berejiklian said. Labor also opposes pill testing.

Joseph Pham died after a suspected overdose at Defqon.

New ReachTel polling for the Sun Herald asked 1627 voters on Thursday night if they supported recreational drug testing at music festivals, with 56.7 per cent saying they did.