Obina Ezeoke, 24, is accused of killing Annie Besala Ekofo, 53, and her nephew Bervil Kalikaka-Ekofo, 21.They were gunned down at a flat in East Finchley, north London, on Thursday shortly after 6.30am.
Scotland Yard said Ezeoke, of no fixed address, is to appear in custody at Hendon Magistrates' Court in north west London on Wednesday.