Police officers were called to a property on Crossways Road, in the Ely area of Cardiff on Friday.
A 64-year-old woman sustained serious injuries after an incident involving a dog and died later at the University Hospital of Wales in the city.
Superintendent Andy Valentine of South Wales Police described it as a "tragic incident".
He said: "The woman's family are understandably extremely distressed and are being supported by specially trained police officers.
"I would like to reassure local residents that this is an isolated incident and a thorough police investigation into what happened on Friday is being conducted.
"I would also like to thank the local community for their support and co-operation during the investigation so far."
The man will appear at Cardiff Magistrates Court on Monday.
A 17-year-old male was also arrested in connection with the incident.  He is on police bail pending further enquiries.
A 23-year-old man has been charged with two offences under the Dangerous Dogs Act after a woman died.