In this study, we aimed to review the demographic, clinical, and laboratory characteristics of patients who were followed up and treated with the diagnosis of serum sickness-like reactions (SSLR) in our pediatric rheumatology clinic retrospectively and emphasize the importance of early diagnosis and treatment. The files of 29 patients who were hospitalized in the pediatric rheumatology clinic between September 2016 and March 2017 with the diagnosis of type 3 hypersensitivity reaction were reviewed retrospectively. Patient records including C-reactive protein, erythrocyte sedimentation rate, serum electrolytes, blood glucose, urea, and liver function were recorded by using the computerized patient database. The gender, age, length of hospital stay, accompanying clinical findings, family history of atopy, preceding infection, and drug usage data were obtained from the files of the patients. Twenty-nine patients with the diagnosis of type 3 hypersensitivity reaction were evaluated. Fifteen (51.7%) of the patients were male and 14 (48.3%) were female. The male to female ratio was 1.07. The age distribution of patients ranged from 18 to 192 months (mean ± SD 100.66 ± 53.75 months). The hospitalization duration was 3–16 days (mean ± SD 5.14 ± 3.20 days). The use of many drugs, especially antibiotics, has increased even in the treatment of viral upper air way infections. As a result, side effects have also increased. The most important of these is SSLR. However, this disease is not well recognized by clinicians.