They never actually say that Mr Bean is autistic in any of the episodes or films. He shows some characteristics that seem to fit autism, for example, how he doesn't like to speak, especially not in full sentences, or even normally two words... However, he does not seem to fit the disorder in general - he just has random characteristics. He understands other people's feelings very well. He seems more perceptive than someone autistic in that respect.
Also, this is just discussing him if he was a real person. We have to remember that Mr Bean is just a character created by Rowan Atkinson (and some others). If Rowan intended him to be autistic, then yes, he is, but I don't believe that that was their intention. They made he for comedy. He is just a fictional character who solves problems in unique ways to be funny! ;) This does not mean that he has a mental disorder. Also, the reason Rowan created a character who doesn't talk much is because he has a huge problem with stuttering, so he prefers not to have to talk himself, or he has to over-pronounce everything he says. Think about Blackadder! And Rowan has said that when he played this character, the other things - his immaturity and selfishness etc. just came naturally...
So yeah, it depends which way you're looking at it - person or fictional character. Hope that helps! ;)
(Oh yeah, if you meant the actor, Rowan Atkinson, not the character, because many people seem to get them confused, then no, he isn't autistic.)