We studied the parameters of the priming effect in preschool children with autism spectrum disorder. We compared the temporal dynamics of the influence of visual object pre-exposure on the accuracy and rate of sound differentiating in children with normal development and with autistic spectrum disorder. We observed significant differences in the expression of the priming effect and the temporal dynamics of facilitating effect in these groups. No significant differences were found between the groups of children with low and high severity of autistic disorder. After the training session with the recognition of simultaneous heteromodal complex signals, the facilitation of reaction to congruent combinations of stimuli with the introduction of incongruent combinations was close to that in children group with normal development. The characteristics of the priming effect manifestation in this case depended on the autism syndrome severity.