Parental misperceptions have been identified as major barriers towards immunizations in children. By use of a German internet vaccine forum for lay persons, a survey was performed to assess current attitudes of parents regarding prevalent issues related to childhood vaccination. Of 6025 participants, 5722 (95.0%) regarded their paediatrician as the most important source of information regarding immunization, followed by leaflets (48.0%), health magazines (44.7%), and the internet (38.7%). Of currently generally recommended childhood immunizations, those against pertussis, Hib and especially measles-mumps-rubella were considered least important by parents. Furthermore, 22.6% of survey participants felt that immunizations are administered "too early" in life and 21.0 and 12.2% thought that overload of the child's immune system and induction of allergies, respectively, would be side effects of immunizations. This survey provided information on prevalent parental attitudes towards immunization, which should be used to plan information strategies to counteract existing misperceptions.