Foster Christian, 53, of Dickens Avenue, Canterbury, appeared before Maidstone Crown Court via video link from Elmley Prison, Isle of Sheppey.
He is charged with the murder of Simon Gorecki, 47, and Natasha Sadler, 40, who were found at a property in the same street on 29 March.
Mr Christian was remanded in custody until 10 June.
He is also charged with two counts of causing grevious bodily harm.
Naomi Toro, 35, of Keyworth Mews in Canterbury, who is charged with assisting an offender, has also been remanded in custody to appear at  Maidstone Crown Court on 29 April.
Another woman, aged 18, who was arrested on suspicion of perverting the course of justice, has been released on bail until 3 May.
A man accused of murdering two people found dead at a house in Kent has appeared in court.