Stress, defined as the body's emotional and physical responses to a particular situation or factors that contribute to it (Fink, 2010), is highly prevalent in children. According to UNICEF (2014), more than one in three children (aged 6 to 18 years) are emotionally distressed and have experienced significant feelings of anxiety and stress that lead them to seek medical attention. It is therefore crucial to be particularly attentive to these warning signals and to implement solutions that will enable the child to better apprehend these stressful situations, to understand his/her physiological functioning and to better manage his/her emotions. The principle of heart rate variability biofeedback is based on the hypothesis that stimulation of the vagal system will lead to an improvement in the heart rate variability level and thus allow, through regular training, better emotional regulation and a significant reduction in stress levels. While this technique, in addition to being easily implemented and affordable, seems to provide many benefits to children, only few valid and well-controlled studies have so far investigated the effects of combining biofeedback and cardiac coherence exercises. Indeed, in a recent systematic review, only about ten articles could be identified. However, the analysis of these articles has enabled us to highlight the significant beneficial effects observed following the use of heart rate variability biofeedback techniques with children, and particularly on children with anxiety disorders (e.g., Knox et al., 2011; McAusland & Addington, 2018) and/or hyperactivity and concentration problems (e.g., Groeneveld et al., 2019; Lloyd et al., 2010). These results will be detailed and discussed, and the perspectives of using this technique specifically for children and adolescents will be considered.