Abstract: Laccases from spent Lentinus polychrous Lev. mushroom compost were extracted, purified and characterized including evaluation of its potential in synthetic dye decolourisation. The enzyme was partial purified by ammonium sulfate fractionation, chromatography on DEAE-cellulose and Superdex 200 HR columns, respectively. The final step purification provided an 18.5% yield and a purification of 48.4 fold. The results from SDS-PAGE indicated that the laccase had a molecular weight of about 32 kDa. The enzyme’s pH optimum was pH 3.0 when using 2, 2-azinobis (3-ethylbenzothiazoline-6-sulfonate) (ABTS) as substrate and the optimum temperature was 55°C. The decolourisation of a model dye, Remazol Brilliant Blue R (RBBR), by the partial purified enzyme was investigated. The results showed that decolourisation ability was highest at about 66% within 3.5 h at pH 4.0.