Seventy- five bulk tank milk samples collected from differentdairy farms in Sharkia govemorate. A survey was conducted todetermine the incidence of Coliforms, Pseudomonas spp. and Yersiniaspp. in bulk tank milk.All milk samples proved to be contaminated with Coliformsusing MPN Iml. Coliform count ranged from 2.0 x 104 to 2.1x 109 witha mean value of2.59 x 108 ± 6.lxl07.Escherichia coli could be detected in 21 ( 28% ) Citrobacterfreundii 20 ( 26.7% ), Citrobacter divers us 2 ( 2.67% ), Klebsiella