The new species Trichoderma martiale was isolated as an endophyte from sapwood in trunks of Theobroma cacao (cacao, Malvaceae) in Brazil. Based on sequences of translation-elongation factor 1-alpha (tef1) and RNA polymerase II subunit (rpb2) T. martiale is a close relative of, and morphologically similar to, T. viride, but differs in the production of discrete pustules on corn meal-dextrose agar (CMD) and SNA, in having a faster rate of growth, and in being a tropical endophyte. This new species was shown, in small-scale, in situ field assays, to limit black pod rot of cacao caused by Phytophthora palmivora, the cause of black pod disease.