The effects of pH value (4.0 to 7.0) on antioxidant ability, free radical scavenging ability and production of antioxidants of methanolic extracts from mycelia and filtrates of Phaeoporus obliquus H011 strain in submerged culture were studied. We found that, pH significantly affected antioxidant activity, scavenging free radical activities, yields of total phenolics and polysaccharide in methanol extracts of the mycelia and the filtrates of P. obliquus in submerged culture. The antioxidant ability and the scavenging free radical activities of methanol extracts of the filtrates were strongest when pH was 6.0, being significantly higher than in other pH treatments (P<0.05). Also, the yields of total phenolics and polysaccharide at pH 6 reached the peak, being 189.9 mg·g^-1 and 47.2 mg·g^-1 respectively, significantly higher (P<0.05) than in other pH treatments. The total phenolics and polysaccharide in methanol extracts might be responsible for the antioxidant activities and free radical scavenging ability of the mycelia and the filtrates of P. obliquus in submerged culture. Higher yields of antioxidants were obtained in the submerged culture as compared with sporophores. Therefore, an alternative approach for producing antioxidants of P. obliquus in a submerged culture could be used in place of solid culture.