The present invention discloses a use of a lactobacillus composition, wherein the lactobacillus composition contains Lactobacillus johnsonii BCRC17010, capable of inhibiting growth of vibrio parahaemolyticus, and adsorbing or invading cells, and having excellent intestinal adhesion, therefore, when the pharmaceutical composition containing an effective amount of Lactobacillus johnsonii BCRC17010 is administrated to an individual infected by the vibrio parahaemolyticus, the effects of continuously inhibiting growth of pathogenic bacteria in an alimentary canal and treating or/and improving the gastrointestinal diseases can be achieved.本發明係揭露一種乳酸菌組合物之用途,其中,該乳酸菌組合物中係含有約氏乳酸桿菌(Lactobacillus johnsonii)BCRC17010,具有抑制腸炎弧菌生長、吸附或侵入細胞之能力,並且具有良好之腸道附著力,因此,藉由投予含有有效量之約氏乳酸桿菌(Lactobacillus johnsonii)BCRC17010之醫藥組合物至被感染腸炎弧菌之個體時,能達到持續地於消化道中抑制病原菌生長,治療或/及改善腸胃道疾病之功效。