OBJECTIVE: To compare cytology and histology on the diagnosis of musculoskeletal neoplasms. METHOD: Fifty eight cases available to evaluation were analyzed both by cytology and histology. The results of the biopsies studied by histology and cytology were compared to the results obtained on the surgical specimen or immunohistochemistry. We determined the percentage of correct results, sensitivity, specificity, positive and negative predictive values and accuracy of each method. RESULTS: Twelve per cent of biopsies were inconclusive by cytology. The percentage of correct diagnosis was 70.7% and 81% (p=.179), the ability to differentiate benign lesions from malignant ones was 84.5% and 93.1% (p=0.18) respectively, for cytology and histology. Cytology showed sensitivity of 87.8%, specificity of 76.5%, positive predictive value of 90%, negative predictive value of 72% and accuracy 84.5%. Histology showed sensitivity of 90.2%, specificity of 100%, positive predictive value of 100%, negative predictive value of 81% and accuracy of 93.1%. The Youden index for cytology was 64.3% and for histology it was 90.2%. CONCLUSION: Despite promising, cytology obtained by thin needle aspiration is less accurate and reliable than the histological evaluation on musculoskeletal tumors diagnosis. Level of Evidence II, Diagnostic Studies.