Streptococcus gallolyticus infection is considered an important septicemic disease in pigeons especially in squabs. In this study the pathogenicity and antimicrobial sensitivity of St. gallolyticus were searched. 141 samples of diseased and recently dead pigeons of different ages were collected and subjected to bacterial examination in order to isolate St. gallolyticus. Sixteen strains were isolated and identified at recovery rate of 11.35%. All isolated strains found following biotype I. The strains were tested In-Vitro for antimicrobial sensitivity to 9 types of antimicrobial drugs. All strains were found highly sensitive to enrofloxacin and flumequine, followed by streptomycin and florophenicol then doxycyclin and lincomycin. A half of strains were sensitive to trimethoprim / sulphmethoxazole, while most strains show high resistance to ampicillin and erythromycin. The test indicates that, most isolated strains (11/16) have multi-drug resistance. Experimental infection with a strain of St. gallolyticus was studied by 2 routs (Intravenous inoculation or crop inoculation) in clinically healthy pigeons. The inoculated microbe dose not cause deaths by any of the 2 routs used for inoculation. Clinical signs as well as post-mortem lesions of experimentally inoculated pigeons by both two routes were recorded and discussed. The inoculated organism was re-isolated from inoculated birds.