Background/Objectives: Autism Spectrum Disorder (ASD) is a lifelong neurodevelopmental condition characterized by social communication impairments and repetitive behaviors. Recent reports show that one in thirty-six 8-year-old children are autistic, signifying a considerable public health concern. According to previous studies, emotional dysregulation (ED) affects 50–60% of individuals with ASD and includes symptoms such as poor emotional control, heightened reactivity, and a low frustration tolerance. The main aims of the current study are to investigate the prevalence of ED among autistic preschoolers (below 6 years of age) and to assess the impacts of gender and intellectual disability on their emotional dysregulation profile. Methods: Data have been collected from three children’s research hospitals in Italy (IRCCS Stella Maris Foundation, Stella Maris Mediterraneo Foundation, and IRCCS Bambino Gesù). Parents of 825 autistic pre-schooled children (mean age: 39.68 months, SD: 10.51 months) completed a general questionnaire and the Child Behaviour Checklist (CBCL), a reliable caregiver-reported assessment tool which provides a dysregulation profile. Results: A total of 30% of the children displayed a severe-to-moderate ED (emotional dysregulation) profile, with these children exhibiting significantly higher emotional–behavioral problems compared to those without ED. Males with ED exhibited greater emotional reactivity than females with ED. However, no significant relationships were found between ED and age, autism severity (ADOS-2), or intellectual disability. Conclusions: The results underline the importance of early, tailored interventions to face emotional challenges in young children with ASD, potentially improving long-term outcomes for this population.