Summary.Plasma samples of alpacas and llamas were analysed by a simple method of two‐dimensional (2‐D) agarose gel (pH 8.6)‐horizontal polyacrylamide gel (pH 9.0) electrophoresis, followed by general protein staining of gels. Genetic polymorphism in both species is described for α1B‐glycoprotein (α1B) and three other unidentified proteins designated prealbumin (Pr), postalbumin 1 and 2 (Pal and Pa2). α1B was identified by cross‐reactivity with antisera for human and pig α1B. Altogether, two alleles of Pr, two of Pa1, five of α1B and three of Pa2 are described. Most of the alleles were present in alpacas and llamas. Alpacas showed a high degree of polymorphism at all four loci. Llamas showed considerable polymorphism at only thePa1andPa2loci. The theoretical probability of exclusion (Pe) of an incorrectly assigned parent was estimated to be about 80% in each species by typing for the six polymorphic plasma proteins reported so far in these species. The given method of 2‐D electrophoresis revealed no fixed differences in protein mobilities that discriminate between ll