Bioassay-guided fractionation of an EtOH extract of the truffle-mimiking mushroom Astraeus pteridis led to the isolation and identification of three new (3-5) and two known (1, 2) lanostane triterpenes and phenylalanine betaine (6). The structures of the isolates were elucidated on the basis of 1D and 2D NMR spectroscopic data, HRESIMS results, and X-ray crystallographic analysis. Compounds 5 and 1 showed moderate activity against Mycobacterium tuberculosis with MIC values of 34.0 and 58.0 microg/mL, respectively.