Fusarium is not typically known as an important wood-degrading fungal genus but rather a litter- and soil-associated fungus that is important for degrading plant detritus. However, the genus is often isolated from wooden materials and is known to possess high lignocellulolytic activity26,27, which was demonstrated by the plate assays in the study. Furthermore, Lavin et al. demonstrated that Fusarium spp. isolated from document collections were able to form biofilms, produce pigments, and decrease pH, which resulted in structural damage and thus constituted a hazard for document preservation28. In this case, the Nanhai No. 1 shipwreck has been waterlogged from approximately 1100 AD until 2007; it is possible that the long time on the sea bottom has changed the structure of the wood so that it is more susceptible to fungal colonization. Moreover, the new conservation conditions, including the increase in oxygen concentration and the reduction in moisture content, will play an overriding role in the colonization of the fungus after the ship is exposed to the museum’s atmospheric environment. Therefore, Fusarium spp. should be regarded as a potential threat to the wooden ship. As a follow-up, we will try to prove that Fusarium spp. actually degrades waterlogged wood of the Nanhai No. 1 shipwreck under laboratory conditions by measuring the weight loss of waterlogged wood samples or their chemical alteration after inoculation of the fungus.