Caring for children with chronic diseases, such as cancer, can impose lots of responsibilities on parents. The present study aimed to investigate time and effort required for care activities among parents of children with cancer in pediatric educational treatment center, Tabriz, Iran. In this descriptive comparative study, parents of 150 children with cancer who were under treatment in pediatric educational treatment center, Tabriz were selected through convenience sampling. Care of My Child with Cancer questionnaire was used to measure the time and effort spent on taking care of children. The data were analyzed using descriptive (frequency, percentage, mean, and standard deviation) and inferential (Friedman test) statistics. The most difficult and time-consuming tasks were physical care activities and usual care for the ill child and other children for the mothers, but emotional factors, information, communication needs, and maintaining family performance while facing disease and treatment for the fathers. The study findings emphasized the effect of childhood cancer on families. While taking care of patients physically, mothers can be provided with information about the disease, treatment, and child care so as to reduce a part of their care burden. Besides, supportive interventions can be used to decrease the fathers’ emotional care burden.