At Fayoum Governorate, blood samples were collected from 124 Friesian cattle to determine the prevalence of brucellosis using Tube Agglutination Test (TAT). Among the examined animals positive titers (more than 1/20) were recorded in 37 animals with a prevalence rate of 29.8%. The prevalence of brucellosis was significantly higher (p < 0.05) in adult (35.8%) than young (12.5%) animals. Infected animals showed signs of late stage abortion beginning from the fifth months to the nine months, retained placentas and mastitis. Microbiological culture from the aborted fetuses, vaginal swabs and milk samples on tryptic soya agar after addition of brucella supplement revealed Brucella abortus in 9 animals out of the 37 serologically positive animals. Application of Polymerase Chain Reaction (PCR) on two blood samples obtained from serologically and bacteriologically negative cows showed positive PCR results. Moreover, PCR on 5 milk samples obtained from cows showed serologically positive and bacteriologically negative results gave positive PCR reactions. In addition blood sample was taken from human attendant in infected farm showed positive serological TAT (Titer 1/160) but results of PCR gave negative results. Finally it can be concluded that PCR is more sensitive technique than cultures and more specific than TAT.