Objectives: Right ventricle (RV) dysfunction has a significant impact on the morbidity and mortality of critically ill patients and is associated with worse outcomes. This study aims to analyze the frequency of echocardiographic alterations of the RV in children undergoing invasive mechanical ventilation (IMV). Methods: Observational study conducted on patients undergoing mechanical ventilation in a pediatric intensive care unit from May 2019 to June 2022. Bedside echocardiograms were performed, and measurements of tricuspid annular plane systolic excursion (TAPSE), tissue Doppler S’ wave, and right ventricle/left ventricle (RV/LV) ratio were evaluated. Results: A total of 146 echocardiograms were analyzed, with a median age of 7 months, 64.4% were infants, and 51.4% were female. It was observed that 24% (35) had TAPSE alterations, 14% (20) had alterations in the S’ wave, and 10.7% (15) had RV/LV ratio altered. Considering RV dysfunction as any of these altered parameters, the frequency was 38.5% (55), with cardiac index weakly correlated with TAPSE (r=0.171; p<0.048) and S’ wave (r=0.281; p<0.001). There was no significant association between echocardiographic alterations and respiratory parameters. Regarding hemodynamic status, the median Vasoactive-inotropic Score was higher in the dysfunction group (7.5 vs. 3; p<0.048), as well as lactate levels (1.74 vs. 1.3; p<0.015). None of the variables were associated with mortality, duration of IMV or length of hospital stay. Conclusions: Echocardiographic alterations of the RV are frequent in children undergoing MV. Echocardiography is a non-invasive tool that aids in identifying this condition, which can impact the management of critically ill patients.