Impact of Polyporus brumalis BRFM 985 pretreatment in non-sterile pilot-reactor on the batch solid-state anaerobic digestion of wheat straw was studied. Pretreatment was carried out on 400 gTS of 1-5 cm autoclaved straw inoculated with 100 g TS of colonized miscanthus pellets. Mesophilic anaerobic digestion was carried out in four 6-L bioreactors. One digester contained only inoculum (digested cattle manure) to estimate endogenous methane production which was subtracted to other results. Other ones contained 111 gTS inoculum and 151.2 gTS wheat straw and 37.8 gTS miscanthus (Control 1); 151.2 gTS wheat straw and 37.8 gTS fungal colonized miscanthus (Control 2) or 189 gTS pretreated wheat straw (Pretreated). Total amount of liquid in each reactor containing a substrate was 2.3 L, composed of tap water buffered with 1.3 g/L NaHCO3 and 1.2 L liquid digestate. Methane productions from controls 1 and 2 were the same at low digestion times. Higher production from Control 1 (up to 6-7%) at high digestion times can be linked to the loss of miscanthus organic matter during pretreatment. In contrast, the methane production increased by 10-20% after straw treatment, showing an improved biodegradability of pretreated straw. However if mass losses occurring during fungal pretreatment are taken into account by referring methane yield to initial TS, pretreatment leads to a methane production decrease (- 7% after 60 days and -9% after 127 days), except at short digestion time where a slightly higher amount of methane (+6% after 15 days) was recovered. In conclusion, fungal pretreatments appeared interesting to increase anaerobic digestion rate and to ease batch SSAD start-up phase but must be optimized to maximise biogas production.