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Different virulence variants of <i>A. pleuropneumoniae</i> are involved in the etiology of porcine pleuropneumonia. The purpose of the present trial was examination of the virulence of the <i>Actinobacillus pleuropneumoniae</i> A-85/14 strain, the type strain of serovar 16, in an animal challenge experiment. Thirty 12-week-old piglets seronegative for <i>A. pleuropneumoniae</i> were allocated into three trial groups each of 10 animals, and they were infected intranasally with 10⁶, 10⁷, or 10⁸ colony forming units (cfu) of the strain, respectively. Clinical signs were recorded twice a day, and the animals were euthanized 6 days after the infection. Typical clinical signs and postmortem lesions of porcine pleuropneumonia were seen in the animals of each trial group; however, they were generally mild, and no significant differences could be seen between the three groups. Even 10⁶ colony forming units of <i>A. pleuropneumoniae</i> A-85/14 strain could induce clinical signs and lesions. Based on these results, the type strain of serovar 16 of <i>A. pleuropneumoniae</i> must be regarded as a typical pathogenic strain of the species.