Many are staying at home because they are afraid of being abused or harassed, said the society.
People with autism can find it hard to interpret other people’s motivations and as a result can be taken advantage of or manipulated, the charity said.
Half of 1,300 sufferers questioned by the society said they had been abused by someone who they thought of as a friend, 37% said they had been manipulated to do something they didn’t want to do by these so-called friends, and 44% said fear of abuse or harassment led them to not wanting to leave the house.
A quarter said they have had money or possessions stolen.
The poll by the charity also revealed neglect. Two thirds said they require someone to prompt them to wash, dress, or eat. But seven in 10 of these sufferers said they had missed meals because they don’t get this support and 86% had not washed.