A boy who died in NSW's central west was autistic and allegedly suffered chronic neglect and abuse, police say.

A man, 42, and a woman, 41, were charged with the murder of the 11-year-old boy after they attended Mudgee Police Station on Thursday.

"We are alleging that he died as a result of severe or chronic neglect and abuse," Homicide Squad commander Michael Willing told Macquarie Radio on Friday.

The boy, who police say was autistic, was found unconscious by emergency services at a home in Kandos, in the early hours of October 1, last year.

He was taken to Rylstone Hospital but died a short time later.

"The boy was an autistic boy and those circumstances are now currently before the court," he said.

The couple have been refused bail to appear at Mudgee Local Court on Friday.