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Two new cytochalasans, Chaetomadrasins A (<b>1</b>) and B (<b>2</b>), along with six known analogues (<b>3</b>&#8722;<b>8</b>), were isolated from the solid-state fermented culture of desert soil-derived <i>Chaetomium madrasense</i> 375. Their structures were clarified by comprehensive spectroscopic analyses, and the absolute configurations of Compounds <b>1</b> and <b>2</b> were confirmed by electronic circular dichroism (ECD) and calculated ECD. For the first time, Chaetomadrasins A (<b>1</b>), which belongs to the chaetoglobosin family, is characterized by the presence of all oxygen atoms in the form of Carbonyl. Chaetomadrasin B (<b>2</b>) represents the first example of chaetoglobosin type cytochalasan characterized by a hydroxy unit and carbonyl group fused to the indole ring. Compounds <b>1</b> and <b>2</b> displayed moderate cytotoxicity against HepG2 human hepatocellular carcinoma cells.