There are measures you can take to help your child with ASD from being bullied. 
 
1.  Role play the situations. Start the conversation to make them feel safe and be as specific as possible.
2.  Make a plan. Tell your child that if someone does something that makes him feel uncomfortable, they can do x, y or z.
3.  Enroll them in a social skills class where they can be around other kids and learn social skills.
4.  Talk to them about their feelings. Kids on the spectrum don’t really understand feelings the same way that we do, or they don’t necessarily identify them in themselves or others.
 
from Lisa D. Settles, Psy. D., licensed clinical psychologist, assistant professor of clinical psychiatry and the clinical director at the Tulane Center for Autism and Related Disorders.