Acid extracts of guinea pig and rhesus monkey anterior uvea, choroid and retina contain immunoreactive VIP. By reversed phase high performance liquid chromatography, the immunoreactive material from these ocular tissues elutes at a position similar to synthetic porcine VIP. Only in the guinea pig anterior uvea is a second smaller peak detected. By size exclusion high performance liquid chromatography, the peptide in the monkey anterior uvea, choroid and retina elutes in the identical position as the synthetic porcine VIP standard with an apparent molecular weight of 3450 daltons. We conclude that a single form of VIP, chromatographically similar to the porcine standard, is the predominant form of the peptide in the eye of guinea pig and rhesus monkey.