Introduction: Cow’s milk protein allergy requires changes in family habits to maintain children’s health. Objective: This study evaluated the effects of cow’s milk protein allergy on the health of children, the quality of life of parents and children, and the adopted parental styles. Methods: Control case study. The case group consisted of children with cow’s milk protein allergy, from eight months to five years old, and those guardians, and the Control Group, for healthy children of the same age group, and their parents. The quality of life of the child (TNO-AZL Preschool Children Quality of Life) and the caregiver (SF-36) were evaluated; parental style (Parental Beliefs and Care Practices Scale); and socioeconomic and health data of the child. The Mann-Whitney test was used to compare the groups (p <0.05). Results: 76 dyads from the case group and 44 from the control group participated. Children with cow’s milk protein allergy had a lower quality of life in the health dimension, worse nutritional status, followed up with a larger number of health professionals. Those in charge of the case group offered less body stimulation to the children. Those in the control group had a lower quality of emotional life. Conclusions: Cow’s milk protein allergy had an impact on the health and nutritional status of children, on the corporal stimulation received by the children, and on the quality of emotional life of those guardians.