Eisenberg's helical hydrophobic moment (<μH>) algorithm was applied to the analysis of the primary structure of amphipathic α‐helical peptide hormones and an optimal method for identifying other peptides of this class determined. We quantitate and compare known amphipathic helical peptide hormones with a second group of peptides with proven nonamphipathic properties and determine the best method of distinguishing between them. The respective means of the maximum 11 residue <μH> for the amphipathic helical and control peptides were 0.46 (±/−0.07) and 0.33 (0.07) (P+0.004). To better reflect the amphipathic potential of the entire peptide, the percent of 11 residue segments in each peptide above a particular <μH> was plotted vs <μH>. The resulting curves are referred to as HM‐C. The mean HM‐C (of the two groups) was highly significantly different such that the HM‐C method was superior to others in its ability to distinguish amphipathic from nonamphipathic peptides. Several potential new members of this structural class were identified using this approach. Molecular modeling of a portion of one of these, prolactin inhibitory factor, reveals a strongly amphipathic α helix at residues 4–21. This computer‐based method may enable rapid identification of peptide of the amphipathic α‐helix class. Copyright © 1989 Alan R. Liss, Inc.