United Nations Special Rapporteur on Torture Mr Manfred Nowak arrives in China today for a two week-long visit to Beijing, Tibet and the western Muslim region of Xinjiang.
He is scheduled to visit detention centres during his visit.
China says it does not condone torture or forced confessions, and has asked courts to think twice before handing down the death penalty lest judgements be based on confessions forcefully extracted in prison.
This summer, China's parliament passed a bill mandating punishment for policemen who torture detainees during interrogation and other offences.
However, rights groups criticise Chinese courts for their arbitrary verdicts and say Beijing must take its commitments to crack down on torture seriously.
China is home to the world's biggest prison population and has a legal system the US State Department says is characterised by mistreatment of prisoners and an "egregious" lack of due process in the use of the death penalty.
China signed the International Covenant of Civil and Political Rights, a cornerstone of global rights law, in 1998 but has yet to join over 150 other countries in ratifying it.