Background: Caring for a loved one can be rewarding but also associated with substantial caregiver burden, developing mental outcomes and affecting happiness. Eventually, these physical and psychological disorders can lead to an imbalance of the autonomic nervous system. Meditation has been found to offer multiple benefits to relieve these disorders and reduce the risk of cardiovascular disease. The aim of this study was to determine the effects of a four-week 16-hour presential meditation program on physiological and psychological parameters and vagal nerve activity in high-burden caregivers, comparing the results with those not receiving this program. Methods: A non-randomized repeated-measures controlled clinical trial was conducted, dividing participants between intervention and control groups by convenience allocation because random assignment was ethically inappropriate. Results: After the meditation program, the experimental group showed a significant reduction in anxiety levels (F= 24.92, p<0.001), a non-significant amelioration of depression levels (F= 1.75, p=0.19), and significantly improved heart rate variability (F= 8.40, p<0.05) and SDNN (F=15.59, p<0.05). Conclusions: Meditation can be a useful therapy to enhance the mental health and autonomic nervous system balance of informal caregivers, improving symptoms of physical and mental overload.