A new monomeric stilbene, halophilol A (1), and a new tetrastilbene, halophilol B (2), along with three known oligostilbenes were isolated from the seeds of Iris halophila. Their structures were established on the basis of the spectral data. The oligostilbene skeleton is encountered for the first time in the Iridaceae family. Bioactivity tests showed that 1 had moderate cytotoxicity against KB and HMEC cell lines (IC50 = 17.28 microM, 22.47 microM respectively), while 2 was inactive.