The invention belongs to the technical field of biology, and particularly relates to heat-resistant laccase, a gene thereof and application. The laccase has the amino acid sequence shown as SEQ ID NO.3. The gene for encoding the laccase has the cDNA sequence shown as SEQ ID NO.2. The gene has the complete nucleotide sequence shown as SEQ ID NO.1. The main laccase (Lac2 laccase) generated by cell fermentation culture is separated out through the fermentation culture of cells with the Lac2 gene, the collection of crude enzyme fermentation broth, and the purification measures of ammonium sulfateprecipitation, ion-exchange column chromatography and the like. The heat-resistant laccase still has high activity at 70 DEG C and can still efficiently degrade malachite green at 70 DEG C. The laccase with the Lac2 encoding gene has quite high heat stability, high pH, organic solvent and inhibitor tolerance and quite broad industrial application prospects, can provide a stable novel laccase source for the industrial application of the laccase, and has good economic benefits and social benefits.