Continuity mistake: During the chase in chariots (2 Romans against Astérix), when the palace is attacked, in one shot, we can see there is only one Roman soldier on his chariot instead two. (01:21:55)
Revealing mistake: When the doctor intercoms the colonel because he cannot get into the medical room for the pregnant woman having nightmares, the camera shows the intercom, which is simply the back end of a desktop computer with a couple of knobs stuck on it. (00:24:50)