Two new cytochalasans, 16α-methylaspochalasin J (1) and 16-hydroxymethylaspergillin PZ (2), have been characterized from the solid fermentation culture of Westerdykella dispersa isolated from the marine sediments. The structures and relative configurations of 1-2 were elucidated by a combination of spectroscopic methods, as well as by comparison with related known compounds. Compounds 1 and 2 showed moderate antibacterial activity with MIC values ranging from 50 to 100 μg/mL.