Based on the transcriptome data of deletion mutants of different genes and different culture conditions of Penicillium oxalicum, the correlation of gene transcription levels in the whole genome was calculated to explore the genes most related to the transcription of cellulase gene and/or xylanase gene in Penicillium oxalicum, including transcription factors, sugar transporters and other functional genes. Overall design: Both cellulase and xylanase are enzymes synthesized in the presence of inducers. Therefore, we believe that the transcription level of genes related to the transcription of cellulase and xylanase genes will certainly change under different culture conditions and the deletion mutants of transcription factors which have an important impact on the production of cellulase and xylanase. Consequently, it is possible to find the most relevant genes for cellulase and xylanase gene expression through correlation analysis of gene transcription levels on important transcription factor deletion mutants and a large amount of transcriptome data under different culture conditions.