The colonization of submerged wood of Bruguiera cylindrica and Rhizophora apiculata by fungi was followed over 60 weeks in Mandai mangrove, Singapore. Seawater temperature ranged from 26—32 °C, salinity from 21— 32%o and pH from 5.91—8.35. Thirty-two fungi, not all from the same wood species, representing 24 Ascomycotina, 7 Deuteromycotina and 1 Basidiomycotina were collected. Very frequent fungi (above 20%) were Didymosphaeria enalia, Lulworthia sp. 1, Lignincola laevis and Aigialus parvus on both timbers; Payosphaeria minuta on B. cylindrica and Aigialus mangrovis and Nais inornata on R. apiculata. Frequent fungi (10.0 — 20.0%) were Halosarpheia marina on both timbers; and Nais inornata, Hypoxylon oceanicum, Deuteromycete No. 456 and Halosarpheia lotica on B. cylindrica. The remaining fungi are classed as infrequent (less than 10%).