Diarrhea is a common fatal disease of neonatal calves. There are many causes of diarrhea while Salmonella and E. coli are the main bacterial causes. One hundred blood and fecal samples were collected for this study; 80 from diarrhetic calves and 20 from apparent healthy calves (the control group). Blood samples were collected from each animal for hematological and biochemical assessment. An increase in total RBCs count, Hb content, total WBCs count, neutrophil percent, hematocrit value, ALT, AST, urea, creatinine, and K level while, total proteins, albumin, globulin Na and Cl decreased in diseased calves when compared to control group. Fecal Samples were bacteriologically examined. Seventy-two bacterial isolates were recovered, they included 22 Salmonella (27.5%) and 50 E. coli (62.5%). Four serogroups were identified for Salmonella including Enteritidis (54.5%), Typhimurium 31.8%, Newport (13.6%), and (9.1%) Anatum. Out of 50 E. coli isolates; 10 serogroups were identified included O26, O103, O127, O119, O86, O111, O157, O44, O158 and O78. Molecular identification of Salmonella strains revealed that InvA, hilA, fimA, and sopB genes were detected in all Salmonella serovars (100%), mgtC (90%), ssaQ and stn (86%) each, and spi4R (81%). E. coli strains revealed that the 16SrRNA gene was detected in all identified E. coli strains (100%), Sta and eaeA (88%) each, Stx1(84%), Vt2e and F41(76%) each, Stx2 (64%).