为深化嗜热纤维素酶资源的开发利用，从西藏尼木热泉分离得到1株产纤维素酶嗜热真菌THN8，根据该菌株在刚果红培养基上产生的透明圈大小，初步判断其产纤维素酶能力。通过形态学和ITS序列分析,鉴定其为Melanocarpus albomyces。在单因素试验基础上采用正交试验确定菌株THN8产纤维素酶的最佳培养基配方及发酵条件，最终获得该菌株产纤维素酶的最佳培养基配方为乳糖92.0 g/L、(NH₄)₂SO₄ 6.0 g/L、K₂HPO4 3.0 g/L、MgSO₄·7H₂O 0.55 g/L，最佳发酵条件为发酵温度58℃、起始pH值5.5、发酵时间4 d，在此条件下菌株THN8的纤维素酶活力达到28.1 U/mL。试验分离出的产纤维素酶嗜热真菌在降解利用纤维素类农业废弃物方面具有重要作用。

 In order to deepen the development and utilization of thermophilic cellulase resources,a cellulase producing fungus THN8 from Nimu hot spring in Tibet was isolated and identified，and the cellulase producing activity of this strain was screened by Congo red culture medium.According to the morphology and ITS sequence analysis,the strain THN8 was identified as Melanocarpus albomyces.On the basis of single factor experiment,orthogonal experiment was used to optimize the cellulase producing conditions of the strain THN8． Finally，the optimal medium formula for the cellulase producing strain THN8 was as follows: lactose 92.0 g/L,(NH₄)₂SO₄ 6.0 g/L，K₂HPO₄3.0 g/L，MgSO₄·7H₂O 0.55 g/L.The optimal fermentation conditions were as follows: the fermentation temperature was 58℃，the initial pH value was 5.5,and the fermentation time was 4 days. Under these conditions,the cellulase activity of the strain THN8 reached 28.1 U/mL.The thermophilic fungus isolated in this experiment plays an important role in the degradation and utilization of cellulose agricultural waste．