An immunohistochemical method utilizing microwave oven treated avidin-biotin complex (ABC) technique was used in this study to detect P53 protein expression in 87 parafin-embedded fibrous neoplasm tissues. The results showed that the total positive staining rate was 20.7%. The positive staining rate in fibroma (FA), dermatofibrosarcoma protuberans (DFSP) fibrosarcoma (FS) and malignant fibrous histiocytoma (MFH) were 0%, 4.0%, 37.5% and 62.5% respectively. The positive staining rate of P53 protein was increased with the increase in malignancy of the neoplasma. The expression of P53 protein was not correlated with the subtypes of DFSP and MFH, but correlated with cell differentiation. Therefore, detection of P53 protein expression may have significant value in the evaluation of malignancy, metastatic potential and the prognosis of fibrous neoplasma.