A mentally-ill Mansfield man admitted killing his 83-year-old mother, when he appeared at Nottingham Crown Court.
Margaret Clapperton was found dead with head injuries at her home in Linton Close, Mansfield, on 28 March 2010.
Anthony Clapperton, 58, of the same address, was arrested after walking into Mansfield police station and giving himself up that day.
Clapperton admitted manslaughter on the grounds of diminished responsibility and will be sentenced on 23 July.
Dawn Pritchard, prosecuting told the court that Clapperton had been examined by two psychiatrists who shared the view that he was suffering from severe mental health problems.
Judge Michael Stokes QC adjourned the hearing for sentence and remanded Clapperton back into custody.