Background/Aims: Brucellosis patients present various non-specific clinical symptoms, such as fever, fatigue, sweating, joint pain, arthritis, myalgia, and headache. Based on the nonspecifity of its clinical signs and symtoms, we decided to evaluate whether mean platelet volume (MPV), neutrophil to lymphocyte ratio (NLR), and platelet to lymphocyte ratio (PLR) will contribute to the diagnosis. Methods: In this retrospective study, we reviewed hospital-records of 60 children with a confirmed diagnosis of brucellosis in Kayseri between January 2013 and January 2016, and compared the hematological parameters; white blood cell (WBC) count, hemoglobin (Hb), neutrophil count, lymphocyte count, platelet count, MPV, NLR, and PLR with 55 healthy age and gender matched children. Also, the well known inflammation markers; erytrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were compared between the patient and control group. Results: We found significant difference among the Hb, platelet count, MPV and NLR values between the patient and control group (p < 0.05). There was no difference between WBC, neutrophil count, lymphocyte count and PLR between the patient and control group (p > 0.05). When the patients were divided into groups as arthritis positive and arthritis negative and compared to the control group; we found that the NLR is more significant in between the arthritis positive and control group (p = 0.013). Also, we found significant difference among the ESR and CRP values between the patient and control group (p < 0.001). Conclusions: The results of this study indicates that MPV and NLR values can be used as markers of inflammation in childhood brucellosis. Also, NLR is more valuable in children with brucella arthritis.