Abstract Background Congenital heart disease (CHD) accounts for nearly a third of all major congenital anomalies. Advances in pediatric cardiology shifted attention from mortality to morbidity and health-related quality of life (HRQOL) of patients with CHD and impact on their families. The purposes of this study were to assess the validity and reliability of the Italian version of the Pediatric Quality of Life (PedsQL) Cardiac Module and to create normative data for the Italian population. Methods This was an observational cross-sectional study of pediatric patients (aged 2–18 years) with congenital or acquired Heart Disease (HD) and their parents. Families were asked to complete the cardiac pediatric health-related quality of life questionnaire (the Italian PedsQL™ 3.0 Cardiac Module) and the generic pediatric health-related quality of life questionnaire (PedsQL™ 4.0 Generic Core Scales). The sequential validation procedure of the original United States version of the PedsQL™ 3.0 Cardiac Module was carried out under the instruction of the MAPI Research Institute. To assess construct validity, Pearson’s correlation coefficients were assessed between scores on the Cardiac Module scales and scores on the scales of the General Module. To determine agreement between patient self-report and parent proxy-report, we used intraclass correlation coefficients (ICCs). To evaluate Internal consistency of items, we used Cronbach’s alpha Coefficient. Results The study enrolled 400 patients. Construct validity is good between PedsQL Cardiac Module total scores and PedsQL total scores (p