Mastocytosis is a rare and heterogenous disease, and in children it is generally limited to the skin and tends to regress spontaneously in adolescence. In this study, demographic, clinical, and laboratory characteristics of pediatric patients with mastocytosis, and also coexisting diseases were investigated. A total of 61 pediatric patients were included in the study. The male-to-female ratio was 2.2, the median age was 2 years (range, 0.25 to 19 y), and the median follow-up period was 2.0 years (range, 0.25 to 19 y). Types of clinical presentation at diagnosis consisted of mainly urticaria pigmentosa (45.9%). Seven patients were further investigated with suspicion of systemic mastocytosis, they were followed up, median of 9 years (range, 2.5 to 16 y), and none of them developed systemic disease. Coexisting allergic diseases were recorded in total 5 patients (8.2%). Three patients had immunoglobulin A deficiency, 1 patient had elevated immunoglobulin E level. A patient developed mature B-cell lymphoma with a heterozygous mutation in c-KIT exon 11. Cutaneous mastocytosis in children may present as a complex disease with different clinical signs and symptoms. Standardized clinical criteria and guidelines for the follow-up of children with mastocytosis are required.