Salmonella species are among the major foodborne pathogens causing diseases of economic and public health implications in poultry and humans globally. This study aimed to determine the occurrence and antimicrobial susceptibility patterns of Salmonella isolates from chickens in poultry farms in Ibadan, Southwest Nigeria. Cloacal swab samples (n = 360) were obtained from chickens randomly selected from 10 poultry farms in five local government areas of Ibadan, Oyo State, from 04 April 2018 to 20 November 2018. Bacterial identification and antimicrobial susceptibility testing were performed using established protocols. Data were analysed using descriptive statistics and Pearson's chi-squared test at P ≤ 0.05 significance level. The overall prevalence of Salmonella was 21.4%. There were statistically significant associations between Salmonella prevalence and the farm location (p = 0.003), age of chickens (p < 0.001), and health status of chickens (p < 0.001). All Salmonella isolates (n = 77; 100.0%) were resistant to cefuroxime. The isolates were also highly resistant to cotrimoxazole (n = 74; 96.1%), chloramphenicol (n = 73; 94.8%), meropenem (n = 72; 93.5%), gentamicin (n = 69; 89.6%), and tetracycline (n = 64; 83.1%). The presence of drug-resistant Salmonella in commercial layer chickens in Ibadan is a potential threat to consumer health as it increases the risk of carcass contamination and pathogen propagation, and limits the options to control and treat infections in humans and animals. Well-integrated national surveillance systems for monitoring Salmonella and antimicrobial resistance in poultry are critical.