A phytochemical study of the asteraceous herb Pulicaria crispa (Forssk.) Oliv. resulted in the characterisation of three guaianolide sesquiterpenes, 2α,4α-dihydroxy-7αH,8αH,10αH-guaia-1(5),11(13)-dien-8β,12-olide (1), 1α,2α-epoxy-4β-hydroxy-5αH,7αH,8αH,10αH-guaia-11(13)-en-8β,12-olide (2) and 5,10-epi-2,3-dihydroaromatin (3). The structures were assigned on the basis of extensive 1 and 2D NMR experiments. Compound 3 exhibited weak antimycobacterial activity against Mycobacterium phlei with a minimum inhibitory concentration of 0.52 mM and cytotoxicity (IC50 of 5.8 ± 0.2 μM) in a human bladder carcinoma cell line, EJ-138.