This is a corpus of semi-spontaneous speech produced by 34 children between 6 and 13 years of age, residents in the Campania region of Italy. Half of the participating children were diagnosed with high-functioning Autism Spectrum Disorder, and the other half were neurotypical children matched for age, gender, and geographical origin. All participants were administered three tasks: a complex image description task, a story-telling task, and a story-retelling task. This resulted in 4 hours and 19 minutes of recorded speech, which were then transcribed and annotated using ELAN. This research project was approved by the Bioethics Committee of the Alma Mater Studiorum - University of Bologna (no. 0173455/2022). Due to the Italian privacy policy, raw data of the corpus (i.e., speech recordings, transcriptions, and clinical information of the participants) is not available. Processed data (i.e., tables of acoustic/rhythmic/lexical/syntactic values, with the name of the speakers masked through an alphanumeric acronym to ensure anonymity) are available from the contact person upon reasonable request.