Sussex Police said the two incidents were reported on Brighton Beach in the early hours of Sunday, September 24.
First, a teenager ‘reported being raped by a man’ on the promenade near the Sea Life Centre, police said.
A spokesperson added: “A second woman, of a similar age, reported being sexually assaulted around the same time on the beach nearby.
"An investigation was launched into both incidents, while the victims were offered support by specialist officers.”
Detectives have since charged a man with rape and another with sexual assault, police said.
Altaib Hamed, 25, of Lewes Road in Brighton, has been charged with rape and remanded in custody, police said.
Police said Bader Saleh, 23, of Percival Terrace in Brighton, has been charged with sexual assault and remanded in custody.
Detective Chief Inspector Luke Kyriakides-Yeldham said: “Both of these women have shown incredible bravery in coming forward and supporting this investigation, which has helped us to bring two people into custody who will now face trial.
“Everyone should be able to enjoy a night out in safety and we remain committed, alongside our partners, to keeping Brighton and Hove a safe place for women and girls and an inhospitable city to those who wish to cause harm.
“To report a crime or any suspicious behaviour on a night out, please contact a police officer or security staff. Always dial 999 in an emergency, or report online or via 101.”