The young teen, who cannot be named for legal reasons, is due to appear in custody at Wimbledon Youth Court on Tuesday (February 2) accused of the murder of Harjit Singh Dulai and for possession of an offensive weapon.
Harjit, 44, was pronounced dead on Wednesday (January 27) after being stabbed by the tennis courts in Rosedale Park, off Albion Road.
The 44-year-old died in hospital, with police launching a murder investigation.
The boy was arrested on Sunday (January 31) by police investigating the murder.
Five men have also been arrested on suspicion of murder as part of the investigation. Four men aged 20, 19, 28 and a man aged in his 40s have been bailed pending further enquiries to a date in late February.
A fifth man aged 39 was released by police with no further action.
Police are still appealing for anyone to come forward who may have information in connection with the murder.
Anyone with information can call the incident room on 020 8785 8099, or contact Crimestoppers anonymously on 0800 555 111 or at crimestoppers-uk.org.