[eng] Purpose: Heart rate variability (HRV) expresses autonomic responses to emotion perception.Although HRV has been examined during affective stimuli in autistic children, no evidence existsabout differences in HRV produced by different stimulus modalities. This cross-sectional studyaimed at comparing HRV during two modalities (affective touch and affective pictures) in autisticchildren and typically developing peers (TDP), and at exploring the factors influencing emotion-related HRV.Methods: HRV time, frequency and non-linear indexes from 20 autistic children and 20 TDP weremeasured during resting state and different affective stimuli: affective/non-affective touch andpleasant/unpleasant/neutral pictures. Children rated stimulus valence and arousal and performeda task of emotion knowledge, and parents completed questionnaires on emotion regulation,behavior and sensory reactivity.Results: Affective touch produced greater HRV responses in autistic children, whereas affectivepictures modulated HRV in their TDP. Age, but not cognition, correlated with HRV in autisticchildren; scores of emotion knowledge, emotion regulation and behavior problems were associatedwith HRV indexes during affective stimulation in autistic children and TDP.Conclusion: Different modalities of affective stimulation produce specific ANS regulation inautistic children. This must be considered for the design of experimental procedures and in thedevelopment and application of intervention protocols.