Subhan Anwar was convicted in February 2009 of murdering his partner's two-year-old daughter, Sanam Navsarka and was serving a minimum term of 23 years in a prison in the West Midlands.
Anwar was found with a broken neck by prison officers at Long Lartin jail in Worcestershire.
Fellow inmates Gary David Smith, 47, and Lee William Newell, 44, appeared before Worcester Magistrates Court today charged with his murder, West Mercia Police said.
"An incident at HMP Long Lartin resulted in the death of prisoner Subhan Anwar. Two prisoners are now in police custody and the matter is being investigated by police," a Prison Service spokesperson said.
Sanam died with 107 injuries on her body after suffering a month of what Bradford Crown Court at Anwar's trial heard was "unbelievable" cruelty.
A post-mortem examination revealed that her arms and legs were broken and there were 36 bruises to her head and neck, 26 to her arms, 10 to her abdomen and two bruises on her thigh revealed where she had been battered with metal poles.
The girl had also been locked in a cupboard and put in a tumble dryer.
She died after fat deposits from her broken bones got into her bloodstream.
Her mother, Zahbeena Navsarka, 21, was cleared of her murder but jailed for nine years on a lesser manslaughter charge.
Anwar and Navsarka, from Huddersfield, West Yorkshire, tried to claim Sanam had stopped breathing after they left her alone in the bath for 10 minutes.
London: A British Asian child killer serving a prison term has been killed in Worcestershire jail after which two of his inmates charged with the murder in a court on Saturday.
First Published: Sunday, February 17, 2013, 00:00