phenyloctadecanol and phenyloctadecanoic acid were produced via lewis acid catalyzed reaction of benzene and oleylalcohol (60 oC) or oleic acid at (80 oC) respectively. A comparison study was achieved for the addition of propylene oxide to both substrates in the presence of base (KOH) and Lewis acid (SbCl5) catalyst. it was found that, the hydroxypropylation of both substrates at low temperature via lewis acid catalyst is more preferably than via the base catalyst. the surface activity of the sulphated products were determined. the results revealed that, the samples produced from alcohol (phenyloctadecanol) show a better surface activity than that from acids (phenyloctadecanoic acid). On the other hand the samples produced from both substrates using Lewis acid catalyst have a better surface activity than that produced with the base catalyst.