In order to investigate the prevalence of Salmonella in Lhasa city and the main causes of Salmonellosis，epidemiological investigation was carried out in 12 chicken farms in 5 counties（districts）of Lhasa city，from April 2015 to September 2016. The results showed as the follows：Among the 1 203 collected samples，589 strains of Salmonella were isolated（positive rate of 48.96%），which indicated the prevalence of Salmonella was high in Lhasa city. Among the tested samples，the positive rates of breeding chicken and hatching egg were 41.00% and 37.00%，respectively，which showed that the vertical transmission of Salmonella was seriously. Among the tested samples，the positive rate of sick chicken was 70.54%，of which the positive rate of adult chicken was 57.63%，the positive rates of environmental and feed samples were 16.67% and 11.60%，respectively. All mentioned above were the major factors for spreading of chicken Salmonella.