A man has been charged with rape after two women were allegedly sexually assaulted in their Adelaide CBD homes by a man posing as a police officer on Friday night.

Key points: Police alleged the incidents occurred within two hours of each other on Friday

Police alleged the incidents occurred within two hours of each other on Friday A 31-year-old was arrested and charged with two counts of rape

A 31-year-old was arrested and charged with two counts of rape The man will appear in the Adelaide Magistrates Court on Monday

Police have alleged a 31-year-old man gained access to a woman's home in Adelaide about 8:30pm on Friday after purporting to be a police officer.

The man then allegedly sexually assaulted the woman and stole money from her house.

Police allege the same man then visited another house in the CBD about 10:30pm and again posed as a police officer to gain entry.

He then allegedly sexually assaulted the second woman before stealing money from the house.

After an investigation, the man from the northern suburbs was arrested by Eastern District detectives.

He was charged with two counts of rape, two counts of aggravated robbery and two counts of impersonating a police officer.

He was refused bail and will appear in the Adelaide Magistrates Court on Monday.