It was collected 2990 blood samples from various ages of chicken of broiler, layer and breeder flocks distributed from different regions of SAR, in order to detect Mycoplasma galisepticum that used in Rapid sero- agglutination test and indirect ELISA test. The study reported sero-prevalence of positive cases using rapid sero- agglutination test 33% in broiler breeder, 1% in broiler chicken and 43% in layer chicken and overall prevalence 24%. By using ELISA test, the reported sero-prevalence values 27% in breeder, 8% in broiler and 33% in layer chicken and overall-prevalence 19%. The study reported markable significant differences between sero-prevalence of broiler chickens in comparing with breeders and layers flocks either using ELISA test or rapid agglutinations test (p=0.00000), as there were no significant differences between layers and breeders flocks using both tests. The study reported high rise- prevalence value in regions of Almobarkat and Damascus compare with other study regions and by highly markable significant differences (p=0.00000).