A dozen human rights experts have signed an open letter to Prime Minister Malcolm Turnbull and NSW Health Minister Brad Hazzard raising concern about a Sydney exhibition featuring preserved human bodies.

The signatories claim there is evidence to suggest the exhibition is using the bodies of executed Chinese prisoners, including political prisoners.

Imagine Exhibitions, the company behind the ‘Real Bodies’ exhibition, sourced their bodies from Dr Hong-Jin Sui, an anatomy expert from China's Dalian Medical University.