The following sixteen Trichoptera species new to science are described and illustrated: Cheumatopsyche navasi sp. n., C. olahi sp. n., C. barnardi sp. n., Potamyia schlingeri sp. n., Leptonema irwini sp. n. (Hydropsychidae Curtis), Nyctiophylax madagassa sp. n. (Polycentropodidae Ulmer), Chimarra apiconigra sp. n., C. blahniki sp. n., C. gassa sp. n., Wormaldia curvus sp. n., W. leviovatus sp. n., W. trispina sp. n. (Philopotamidae Stephens), Goera madagassa sp. n. (Goeridae Ulmer), Lepidostoma asymmetrica sp. n. (Lepidostomatidae Ulmer), Pisulia lata sp. n. and P. magna sp. n. (Pisuliidae Ross). The families Polycentropodidae and Goeridae are recorded from Madagascar for the first time. With this report, 204 Trichoptera species are now known from the island. A first key to adults of the known families and genera of Madagascan Trichoptera is provided.