ObjectiveTo investigate the expression of ErbB3 and Flotillin-2 in osteosarcoma biopsies and possible clinical pathology significance. MethodsThe tissue biopsies were harvested from 38 osteosarcoma patients and 13 osteochondroma patients between September 2009 and March 2014 for immunohistochemical staining. The ErbB3 and Flotillin-2 expressions were observed in osteosarcoma and osteochondroma biopsies, and the correlation and the relationship to the clinical and pathological features were analyzed. ResultsThe expression levels of ErbB3 and Flotillin-2 in osteosarcoma were significantly higher than those in osteochondroma (P<0.05). The high expressions of ErbB3 and Flotillin-2 had good consistency in osteosarcoma (Kappa=0.434, P=0.000). The high expression of ErbB3 was positively correlated to the clinical stages and lung metastasis (P<0.05), but it was not associated with gender, age, tumor location, and size (P>0.05). The high expression of Flotillin-2 had no correlation with clinical and pathological features (P>0.05). The influence factors of patients' overall survival included clinical stages, lung metastasis, high expression of ErbB3, and tumor size (P<0.05). Only lung metastasis and high expression of ErbB3 were independent factor affecting overall survival (P<0.05). ConclusionThe ErbB3 and Flotillin-2 express highly in osteosarcoma and the high expression has good consisitency. Besides, the high expression of ErbB3 is associated with the clinical stages and lung metastasis, indicating a poor prognosis for osteosarcoma.